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August 8

Escalators changing directions

One day the escalator is going up and the next day down. Why? Anna Frodesiak (talk) 02:13, 8 August 2017 (UTC)[reply]

Because somebody flipped the switch that reversed it's direction.--Jayron 32 02:23, 8 August 2017 (UTC)[reply]

Excellent answer, Jayron32. :) Now, why did they flip that switch? Anna Frodesiak (talk) 02:32, 8 August 2017 (UTC)[reply]

In response to the Q, "Why did the Titanic sink ?", Jayron's answer would no doubt be "Because it was full of water." :-) StuRat (talk) 03:36, 9 August 2017 (UTC) [reply]

It's possible that they adjust the direction to match traffic flow. So, for example, if they have 3 escalators, they may have 2 going up and one down when people are coming into the building, and the reverse when they are leaving. Unlike changing the directions on roads, this operation should be fairly simple. Just put up a barrier blocking people from getting on, wait until everyone is off, then flip the switch and remove the barrier. StuRat (talk) 02:41, 8 August 2017 (UTC)[reply]

They might do this at large sports venues, for example. ←Baseball Bugs ^{What's up, Doc?} carrots→ 02:51, 8 August 2017 (UTC)[reply]

Yes, it's a standard thing to do at locations like that, and similarly in public transit stations where some escalators will run one way in the morning peak and the other way in the evening. (Details will depend on the traffic at the specific location, of course.) With the ones that I've seen, there may be a small sign telling staff what time each day to change it, next to the up/down switch (which is key-operated, by the way). But Anna says this isn't the case she's asking about. --69.159.60.147 (talk) 05:16, 8 August 2017 (UTC)[reply]

I'm not sure that's it. I see in lots of malls, a pair of escalators switching up to down and down to up. These are quiet malls with no traffic-flow reason to do this. Could this be about the gears and evening out wear from continuous single direction usage? Or is it psychological to shake up and wake up the people, or make them flow in a different direction when they disembark, like to make them see now products? Anna Frodesiak (talk) 02:58, 8 August 2017 (UTC)[reply]

They also switch up directions so that the escalators wear evenly. .--B8-tome (talk) 02:52, 8 August 2017 (UTC)[reply]

Edit conflict. I just guessed what you wrote! See above. Are you sure though? Thanks. :) Anna Frodesiak (talk) 02:58, 8 August 2017 (UTC)[reply]

If you want to be sure, you'll have to ask the building management people. --69.159.60.147 (talk) 05:16, 8 August 2017 (UTC)[reply]

Many modern escalators have sensors to detect people getting on. If no-one uses them for a while, they shut down, and re-activate in the useful direction when the next person gets on. --Stephan Schulz (talk) 12:41, 8 August 2017 (UTC)[reply]

Assuming that's true, it sounds like trouble waiting to happen. And what does it do if two people get on opposite ends at the same moment? ←Baseball Bugs ^{What's up, Doc?} carrots→ 00:08, 9 August 2017 (UTC)[reply]

There is no such thing as two events happening "at the same moment" for a control computer. One or the other will win. If it goes your way, you grin apologetically at the other person. If not, you glare at them while you wait or use the stairs, which are usually next to the escalator. --Stephan Schulz (talk) 04:45, 9 August 2017 (UTC)[reply]

Metastability in electronics is an inevitable result of any attempt to map a time-continuous domain to a clocked one. Blooteuth (talk) 12:13, 9 August 2017 (UTC)[reply]

It will depend on the tolerances of the device. When I reset my cable box, I have to push three buttons at once, with two hands. I'm sure that I'm not literally pushing all three of them at the same moment, but it works. Also, I'd like to see a citation for someplace where escalators oscillate between up and down depending on where someone steps on it. I would think that customer irritation is a big price to pay for being too cheap to build a second escalator. ←Baseball Bugs ^{What's up, Doc?} carrots→ 18:55, 9 August 2017 (UTC)[reply]

Not a high-quality source, but a blog report from an expat living in Munich. These are totally normal in Germany in places with little traffic or in situations where traffic streams change depending on the time of day. Remember that Europe has public transport, and these are part of the infrastructure, not a luxury to impress customers ;-) --Stephan Schulz (talk) 21:45, 9 August 2017 (UTC)[reply]

The comments are good evidence for why it's a stupid idea. ←Baseball Bugs ^{What's up, Doc?} carrots→ 22:52, 9 August 2017 (UTC)[reply]

About as stupid as the idea that we don't all live in 40 room villas on beautiful mountain tops and commute to work from our personal airport in a custom 747. Or to build 6 lane highways where a 12 lane highway would avoid all traffic jams. In the real world, resources are limited and we tend to prioritise how we use them. Perhaps it's not yet clear: There always are normal stairs next to the escalator. Most people get to ride (because the escalator statistically follows the traffic direction), the others can wait or walk. Nobody is doomed forever... --Stephan Schulz (talk) 05:51, 10 August 2017 (UTC)[reply]

The comments in that blog illustrate why it's a stupid idea: it aggravates people. It's typical European authoritarianism: Here it is, live with it, get used to it. ←Baseball Bugs ^{What's up, Doc?} carrots→ 19:56, 12 August 2017 (UTC)[reply]

When you push those 3 buttons, the device registers the fact that each is being held down continuously. That is totally different from the situation we're talking about here, where a device reads the state of each escalator's infra-red detector in turn. Only one will be successful, even if another one is triggered a fraction of a microsecond after being read and before the reading of the other. Polling on a rotational basis like that can result in only one being first. This is the basis of all computer programs which run through a set of commands and loop back to the start. No two commands can be read at the same time because the reading of them is timed in rotation by the system clock. Akld guy (talk) 21:21, 9 August 2017 (UTC)[reply]

What's your evidence for how cable boxes work? ←Baseball Bugs ^{What's up, Doc?} carrots→ 22:50, 9 August 2017 (UTC)[reply]

I've been reading and thinking about this up/down phenomenon. I would like to add something. It is all over the city in different malls. And it may be just disorganized workers. The person who turns the key each morning may be different on different days. He turns the key maybe left, maybe right. If it goes up, then he makes the other go down. No system. That would fit where I live perfectly. There's probably a rule for this -- something like Occam's razor or Hanlon's razor. Then again, I could see (I suggested this above) shops at the foot of an escalator asking management to make people disembark there to attract more customers. Anna Frodesiak (talk) 08:42, 11 August 2017 (UTC)[reply]

Do escalators follow the rule of the road? That is, in this country at the point you board the escalator the one running in your direction of travel is usually on the left as you face it. 79.67.91.37 (talk) 10:45, 12 August 2017 (UTC)[reply]

No, they do not, not in China anyway. :) Anna Frodesiak (talk) 11:09, 12 August 2017 (UTC)[reply]

(edit conflict)And again, on the London underground the rule is "stand on the right", i.e. traffic is flowing on the left hand side. This shows the convenience of the "keep left" rule on the highway, since it is more convenient for right - handed people (the majority) to grip the handrail with the left hand while holding and manipulating the ticket with the right. 79.67.91.37 (talk) 11:14, 12 August 2017 (UTC)[reply]

Neuroscience question

Is it possible to remove consciousness (like the feeling of under anaesthetic), but keep your body alive and functioning normally in everyday life? I.e. is it possible to turn a person into a meat machine? Why does consciousness even exist? If materialism is correct there shouldn't be any consciousness. It would reduce a lot of suffering in this world if people can do this, unless dualism/idealism is correct. Money is tight (talk) 05:31, 8 August 2017 (UTC)[reply]

Vital body functions can remain alive when the patient is in coma, yes. Of course that is not the same as functioning usefully. Unconsciousness, coma, brain death and autonomic nervous system may be useful. As for the part about materialism and machines, it is indeed expected that neuroscience may eventually explain consciousness. Parts of consciousness are being understood but a lot remains to be discovered. You appear to infer that the source of consciousness would be a hypothetical soul or the like. We can invent such explanatory devices, symbols and concepts for things that are unknown. We also do this as part of science, but more rationally. Some hypothesize that the impression of self-consciousness is an illusion. Also see hard problem of consciousness, existence of God and problem of evil. —Paleo Neonate – 06:38, 8 August 2017 (UTC)[reply]

Maybe it is possible. If an evil scientist had selectively removed consciousness from half of the human race but left them functioning exactly as usual in all other respects (including stating that they were actually conscious when asked) then how could you tell ? See philosophical zombie. The materialist response is that a philosophical zombie is a logical or physical contradiction - like a three-sided square or dry water. Gandalf61 (talk) 08:24, 8 August 2017 (UTC)[reply]

An Induced coma by barbiturates such as Pentobarbital and Thiopental can be maintained (e.g. for brain surgery, 7-14 days with monitoring by an anaesthesiologist) with some risks which are noted here as: Myocardial depression, Increased in venous capacitance, Impaired gastrointestinal motility, Increased hepatic microsomal activity, Possible allergic reaction and Impaired immune response. Blooteuth (talk) 10:05, 8 August 2017 (UTC)[reply]

Why focus strictly on materialism? That is a subset of desire, which is one of the four noble truths. 209.149.113.5 (talk) 15:02, 8 August 2017 (UTC)[reply]

You may be confusing ontological materialism with economic materialism. Gandalf61 (talk) 15:15, 8 August 2017 (UTC)[reply]

Materialism and consciousness are friends. People who formulated materialism had consciousness. --AboutFace 22 (talk) 16:04, 8 August 2017 (UTC)[reply]

That's only trivially true. They also had pancreases and eyebrows and mothers, but that doesn't mean that knowing that leads us to a deeper understanding of materialism. Post hoc ergo propter hoc and all that jazz. --Jayron 32 16:11, 8 August 2017 (UTC)[reply]

There is no problem of understanding materialism. There is a problem of understanding idealism and religions. I subscribe to the quantum theory of consciousness[1]. --AboutFace 22 (talk) 16:41, 8 August 2017 (UTC)[reply]

Which is no less based on a pure-faith belief than any other religion, except it uses sciencey words so it makes the athiests feel better. --Jayron 32 18:38, 8 August 2017 (UTC)[reply]

I wouldn't say that athiesm requires justification, or that quantum mind is pure faith, but it is pseudoscience (or at least, a far fetched hypothesis for now). —Paleo Neonate – 20:22, 8 August 2017 (UTC)[reply]

Or just give up on materialism and accept that there only exist a mathematical multiverse. This is a set of all algorithms, one of these algorithms will be me at precisely this moment when I'm writing exactly this part of this sentence. Another algorithm is me a few seconds later writing this part of the next sentence. And yet another algorithm is Jayron32 writing to AboutFace 22 that what he says is no better than any other religion. Note here that the algorithms contain all the information about what the person (or some other entity) is aware of, it doesn't imply the existence of an external world, it encodes the external world indirectly as that's contained in whatever the person is aware of. Count Iblis (talk) 20:18, 8 August 2017 (UTC)[reply]

solipsism Gem fr (talk) 13:17, 10 August 2017 (UTC)[reply]

See Zombie#Haitian_tradition. This holds that it is possible, by use of a psychoactive substance, to disable their decision making processes, rendering them highly susceptible to suggestion. Not medically verified to be true, though, perhaps because voodoo priests/priestesses tend to be highly secretive about their methods. (This tradition also holds that zombies rise from the dead, but far more likely they were just in a deep coma from the substances ingested, noting that in Haiti the air temp and body temp are often close, so as to make determining death by body temperature impossible.) StuRat (talk) 04:16, 9 August 2017 (UTC)[reply]

Your question cannot be answered without a proper definition of consciousness and "normal everyday life". You'll find Self-awareness of interest, i guess.

"If materialism is correct there shouldn't be any consciousness" is quite a strong assumption, why would you believe that? Gem fr (talk) 13:17, 10 August 2017 (UTC)[reply]

The question sounds like the questioner is reifying conciousness - probably they believe in something like a soul that might be removable. But this is a belief we don't need to deal with to answer the question; the behaviors of people who take Ambien or who sleepwalk demonstrate that all sorts of complex behaviors are possilble while unconscious. - Nunh-huh 21:08, 10 August 2017 (UTC)[reply]

Who said sleepwalkers aren't conscious? And as for the materialism no consciousness thing, it's intuitive that in a Newtonian materialistic world there should be no consciousness (which has lead people like Dennett to believe consciousness is just an illusion). I'm saying, if materialism is correct we must be able to turn off consciousness, and that would reduce so much suffering (maybe because I've been through so much myself, I wish I had an on/off switch to my consciousness). Money is tight (talk) 02:39, 11 August 2017 (UTC)[reply]

The problem is that you, and some respondents, have conflated two discrete meanings of the term "conscious" which might as well be considered little more than homonyms for purposes of this sort of discussion: 1) the general topic of the sensation of subjective experience, and 2) the concept of the much narrower state of mind of being "awake", a specific experience which in every day dialogue we treat as "more real" or "more conscious" than other states of mind we spend our life in. Your answers (such as exist) vary a little depending on which definition were are utilizing in parsing the questions themselves. I'll answer your originally inquiry shortly, when I have time to spare.

As to the somewhat separate issue of a mechanistic Newtonian universe precluding consciousness as an objectively real phenomena, that's a complex topic, but suffice it to say that while it may seem like an intuitive assumption to you, experts (be they cognitive scientists or metaphysicians) are far from settled on the matter--to say nothing of people generally, of course! I also agree that you don't seem to be adequately explaining the intermediate causal relationships that lead you to believe that materialism is incompatible with the view that consciousness is in fact a "real" phenomena, albeit one that is poorly understood in physical terms at present. If you are referring to the hard problem of consciousness, then yes, that's a real quandary. Well, that's an understatement, actually. It's probably in fact the greatest quandary in the history of human inquiry. But not all researchers or philosophers agree that it's established that consciousness is not an empirical reality, however confusing the question of how it arises out of physical matter. And I think it's more accurate to say that Daniel Dennett claims not that consciousness doesn't exists in any sense, but that the nature of the questions we ask about it are often non-pragmatic/unuseful. Snow ^{let's rap} 09:15, 11 August 2017 (UTC)[reply]

Not sure I understand what you mean, but it seems to me that booze, drugs and even sleep are fairly common and effective ways to "to turn off consciousness", and "reduce so much suffering" (or at least try to, i am not sure it works very well in this respect...), so obviously consciousness needs a material element to function, for sure.

I am pretty sure that "suffering" is a word that can be applied to unconscious beings (like an oyster being eaten alive, or a comatose human), so turning off consciousness wouldn't work.

As far as i understand Buddhism, it even say that suffering is consequence of LACK of consciousness, not too much of it (please correct me if wrong). In fact, AFAIK, all spiritual ways tries to reach some higher level of consciousness as a way to reach real happiness, prevent or fend off sufferings.

Gem fr (talk) 10:32, 11 August 2017 (UTC)[reply]

I think you're going to find that perspectives vary considerably between particular traditions and idiosyncratic perceptions, when it comes to such spiritual matters. For a certainty, there are strains of Buddhism that would argue that the "higher level" consists of letting go of the notion of subjective experience, and the illusion that one is a separate thing for the rest of reality. And indeed, some perspectives might even find the notion of qualia and perception of the physical world to be a trap. These issues are a matter of longstanding debate in certain ascetic traditions, needless to say.

As to the other, much more (well, ok, slightly more) empirical matter, I don't think most neuroscientists would agree with you that an oyster is a fundamentally "unconscious" creature, when we are looking specifically at the issue of pain. It has a nervous system with both internal and external sensory inputs. It has a rudimentary kind of consciousness, or at least is presumed to in the way most animals with such biophysical systems are assumed to. It may not include anything approaching the human capacity for abstract knowledge or even the sensorium/level of outward perception/sense of experience of an animal of intermediate neural complexity (let's say, for example, a bee), but it presumably does "feel" in respects other than pain. Snow ^{let's rap} 11:02, 11 August 2017 (UTC)[reply]

Sure oysters feel; Scallops can even see (a rudimentary sight, indeed, but a sight anyway). I am just pretty sure OP doesn't consider these as "conscious", since according to his question consciousness may not be not required to live a normal life. Then again, a proper definition of consciousness is lacking. Gem fr (talk) 11:43, 11 August 2017 (UTC)[reply]

This also reminds us that nervous systems evolved (evolution of nervous systems, evolution of the brain, evolution of human intelligence) along with bodies for a long time (so did neurons before and after complex nervous systems existed), making hypotheses like quantum mind or higher souls which require an advanced level of sentience to possess/assess, less likely. Animal cognition is also interesting... —Paleo Neonate – 14:00, 11 August 2017 (UTC)[reply]

You can also turn this around and start with sensations, consciousness and then consider the problem of localizing yourself in some state given everything you aware of. So, given what I experience right now, I can locate myself in a place where there exists a human body that I consider to be me that's typing this sentence in a computer that's logged into Wikipedia. But the far more rudimentary consciousness of an oyster probably won't be precise enough to locate itself as being inside the body of an oyster at roughly the place and time as we can observe it. It could just as well be some other similar creature swimming in an ocean on a planet similar to Earth. In case of humans, if the universe is large enough or if there exists a multiverse, then we'll have copies in places that need to be far more similar to our current location, what matters is that we are not aware of the difference.

This then means that consciousness cannot be attributed to the precise microstate of the system, as the conscious experience does not contain enough information to locate itself in a precisely defined physical state. Count Iblis (talk) 18:36, 11 August 2017 (UTC)[reply]

Cooling a CCFL bulb without straining the glass

I want to make a floodlight from salvaged CCFL lamps. Despite their name, they do generate heat and I'm going to be using them in high-density so I need to cool them (their efficiency drops off beyond about 30 °C) and I'd like to do it passively if possible (mostly because of the noise). The way I'm considering doing this is affixing the glass tubes to an aluminium panel (thickness not determined), possibly using thermal adhesive or possibly a cheaper adhesive. My concern is that with cooling on one side of the glass tube, it could lead to stress and fracturing which would destroy the tube. Is that a valid concern? --145.255.246.78 (talk) 06:23, 8 August 2017 (UTC)[reply]

Yes it's a valid concern. Consider immersing the lamps in a transparent oil. Blooteuth (talk) 09:43, 8 August 2017 (UTC)[reply]

I am not an expert, but perhaps immersing high voltage devices in oil could give rise to some safety or reliability concerns ? Gandalf61 (talk) 10:13, 8 August 2017 (UTC)[reply]

Oil immersion is commonplace for high voltage transformers and contact breakers. Blooteuth (talk) 11:45, 8 August 2017 (UTC)[reply]

Indeed. But the fact that some high voltage devices are designed to be immersed in oil does not give me confidence that taking some other high voltage device that is not designed for this and immersing it in oil is either safe or sensible. Gandalf61 (talk) 12:28, 8 August 2017 (UTC)[reply]

Oil is a poor coolant for this task. In large devices, it circulates and the heat transfer is by convection. Here you need something that's useful by conduction. There are such thermal tapes available, they're now widely used for mounting COG (Chip On Glass) LEDs onto aluminium heatsinks. They're also slightly flexible, to avoid straining the glass. Andy Dingley (talk) 14:47, 8 August 2017 (UTC)[reply]

^^ That is the answer, I think, but I'm rooting for one of those misting devices they use for produce at Wal-Mart. You would try to make sure the ends are sealed up and then you have a flooded floodlight dripping gentle shining warm ?high voltage? rain. Would look really cool... Wnt (talk) 18:32, 8 August 2017 (UTC)[reply]

I guess you're joking but I'd still like to understand what you're saying. The misting device would be fed oil that leaks from the enclosure? In any case, I was thinking of using thermal adhesive from a tube to adhere the glass CCFLs to the aluminium sheet. I figure that will be much thinner than using even a 0.5 mm thermal pad. --145.255.245.164 (talk) 22:08, 9 August 2017 (UTC)[reply]

Well, I was thinking if you are talking about oil, why not water? In theory, the electrical bits can be insulated, and if the mist is fine enough, the water shouldn't impose large temperature variations. And of course a water line can keep flowing at a high rate to keep cooling things down. Wnt (talk) 00:30, 10 August 2017 (UTC)[reply]

Glass is a thermic isolator. Aluminium alloys have a typical Thermal conductivity (W·m⁻¹·K⁻¹) of over 100. Glass has a typical thermal conductivity of 0.5 - 2! Thus you can not use glass as part of a heat "bridge" or cooling "chain". It does not matter much if you cool the glass with aluminium, copper or graphene. Its like putting a stretch of plastic between 2 copper cable ends and then ask if the electric current would improve if you would use gold contacts on the plastic ends. --Kharon (talk) 11:30, 8 August 2017 (UTC)[reply]

The glass is non-negotiable since the body I want to cool is made of glass. Attaching it to an aluminium sheet with some heatsink attached would maintain a temperature gradient. One option is glass and aluminium and the other is glass and air. The aluminium would greatly increase the surface area in contact with air. 129.215.47.59 (talk) 14:48, 8 August 2017 (UTC)[reply]

The quoted thermal conductivity of glass is 0.8 to 0.93 W·m⁻¹·K⁻¹ A (disputed) diagram at the article Thermal conductivity shows it relative to other materials. Blooteuth (talk) 12:08, 8 August 2017 (UTC) (edited after vandalism Blooteuth (talk) 11:57, 9 August 2017 (UTC))[reply]

The best way to keep the tubes cool would be to allow natural convection between them. What orientation will you have them in? Dbfirs 12:53, 8 August 2017 (UTC)[reply]

They will be arranged all in parallel. I made this useless animation to try to compare active versus passive approaches. Since I want these floodlights to illuminate my dumb YouTube videos (in progress), I don't really want the noise of the fans. I'm planning on having 50-70 in parallel, representing about 200-300 W of heat yet I need to keep them below 60 °C maximum (40 °C would be better) 129.215.47.59 (talk) 14:48, 8 August 2017 (UTC)[reply]

Will they be horizontal or vertical ? I would expect convection to work better if they were vertical, provided there is a sufficient air gap between each tube, it's neighbors and the housings.

As for fans, they can be made to be silent, provided they are large and slow moving. I have large box fans hooked up to a dimmer switch so I can reduce the speed and hence noise down to a whisper. StuRat (talk) 02:53, 9 August 2017 (UTC)[reply]

If the floodlight project is for making videos, I suggest first checking with your video camera whether CCFL illumination is adequate regarding flicker and colour rendition. Blooteuth (talk) 12:03, 9 August 2017 (UTC)[reply]

I probably won't go through the hassle to make my own floodlight, but, anyway...

I very much doubt that you will cool the lamp by gluing them to an aluminum panel, video projectors would have used this kind of system if it worked. Speaking of which, this article has DIY links, that cope with the very same cooling issue that you have (same power range), so you will find them of interest (e.g. [2] ).

You could find interest in computer fans a,d computer fan#Alternatives, to, as they do the job of pulsing away 100s W without uncomfortable noise

Gem fr (talk) 12:54, 10 August 2017 (UTC)[reply]

Lard diet

I've been reading about "no carb" diets and I was wondering how long could a human survive eating nothing but lard? — Preceding unsigned comment added by 190.117.188.223 (talk) 09:40, 8 August 2017 (UTC)[reply]

As long as it takes for one of these diseases to kill you. It's probably somewhat variable based on your particular biology, but you'll die of one of those. --Jayron 32 10:51, 8 August 2017 (UTC)[reply]

Are you sure of that? I can't help wondering if Kwashiorkor or some effect of protein deficiency will kill you first, especially for a child. And what about Mineral deficiency? This may depend on your precise water and lard, but what about a sodium or potassium deficiency? P.S. I'm assuming that this isn't excluding drinking water since I suspect you'll probably quickly die of dehydration if you only eat even unrendered lard and don't drink anything. Nil Einne (talk) 15:53, 8 August 2017 (UTC)[reply]

That'd work too. There's lots of ways to day of malnutrition. --Jayron 32 15:58, 8 August 2017 (UTC)[reply]

Or even ways to die of malnutrition tomorrow ; -) Aspro (talk) 18:21, 8 August 2017 (UTC) [reply]

Pronounce "day" the Aussie way and it works. ←Baseball Bugs ^{What's up, Doc?} carrots→ 19:45, 8 August 2017 (UTC)[reply]

I believe that you would die of Hyponatremia before any of the other conditions mentioned gets you. Under the right conditions, [3] severe, life-threatening hyponatremia can occur in a matter of hours.[4] Too-rapid restoration of normal sodium levels may also cause trouble.[5] --Guy Macon (talk)

Wouldn't the hyponatremia be due to a sodium deficiency arising from insufficient dietary intake? Assuming as I said above they had a sufficient but not excessive water intake and weren't trying to run a marathon or something. Yes it may not normally be the sole cause, but it seems to me it would be in this case. Nil Einne (talk) 04:16, 9 August 2017 (UTC)[reply]

You'll survive longer on blubber. Count Iblis (talk) 20:25, 8 August 2017 (UTC)[reply]

fasting, starvation and Starvation response will be of help. specially Starvation response#timeline and Starvation response#Biochemistry

You can survive several month on your own lard ("fasting" as several examples), the lifespan will depend on your health and what you drink, since it will bring some of the necessary nutrients (like aforementioned sodium).

according to Starvation response#Biochemistry, death occurs when you run out of energy (fat) or, when fatty enough, of proteins; you usually have enough micro-nutriments (vitamins, mineral, etc.) to don't run out of these (also the lack of them will make you more susceptible to death by disease). Obviously eating lard will ensure you only die out from a lack of proteins, so the best answer is probably "longer than if you don't eat lard, but not much".

Gem fr (talk) 12:05, 10 August 2017 (UTC)[reply]

Ventricular fibrillation by palpation

Not a medical request, just curiosity Is it possible to detect ventricular fibrillation by chest palpation instead of electrocardiogram? Would the palpating person sense quivering instead of beating? 212.180.235.46 (talk) 17:10, 8 August 2017 (UTC)[reply]

Some people arrive at the hospital with a chief complaint that indicates they are feeling the effects of arterial fibrillation. Descriptions I've heard are skipping a beat, hearing a thud, or just chest pain. Ventricular fibrillation is different. With ventricular fibrillation, the heart pumps little to no blood. Cardiac arrest and unconsciousness follows very quickly. Therefore, I seriously doubt the person will be able to say what they felt. Of note, there will be no transfer of short-term memory to long-term memory. So, they will have no memory of the few minutes before losing consciousness. Therefore, they will not be able to describe what they felt. 209.149.113.5 (talk) 17:39, 8 August 2017 (UTC)[reply]

[1] you mean atrial fibrillation, not arterial. [2] the questioner seems to be asking if a second person (that is, the examiner, rather than the person with ventricular fibrillation him or her- self) could detect ventricular fibrillation. A person with ventricular fibrillation would be pulseless, but this is usuallly determined by palpating an artery rather than the heart per se. And there are other pulseless rhythms (pulseless electrical activity). Generally, if someone is in ventricular fibrillation, the examiner will be more interested in hooking them up to a monitor/defibrillator than in practicing their palpation skills. - Nunh-huh 18:05, 8 August 2017 (UTC)[reply]

August 9

timing belt idler wheels

I have a bunch of timing belt idler wheels that I want to mount onto a plate[6]. The ball bearings inside these have a inner diameter of 5mm. What's the "proper" way of mounting them?

If I use a screw to mount them (like the left side of [7]), then the screw will improperly contact the side of the wheel, and the wheel will grind against the plate.

I tried putting a 5mm diameter dowel pin inside the wheel and mounting the dowel pin instead (right half of [8]). But the problem is that dowel pins are always oversized, so the mere act of the putting in the dowel pin has managed to destroy the bearings. Mũeller (talk) 05:15, 9 August 2017 (UTC)[reply]

I think the idea of the screw, or a bolt, is the right way to go. You need two flat washers whose outer diameter is no greater than the outer diameter of the inner race. Place one washer between the idler and the plate, and the other under the head of the bolt. When you tighten up the bolt, the inner race will be placed under compression and will not turn, leaving only the outer race to turn around it. You need good quality washers to avoid uneven compression and deforming of the inner race. Akld guy (talk) 06:20, 9 August 2017 (UTC)[reply]

Thanks. I'm having a hard time finding the right washers. ID is 5mm, and the outer diameter of the inner race is only 6.3mm. The smallest M5 washer I can find is 8mm. Mũeller (talk) 07:49, 9 August 2017 (UTC)[reply]

Here's the cheapest nastiest solution. http://www.unitedfasteners.com.au/media/images/product/product_tmp/large/UN0104_2861351072354.JPG I suspect you will encounter problems with the the bolt working loose in the plate, really you should be supporting both ends of the bolt. You may get away with it depending on the usage profile. Greglocock (talk) 08:14, 9 August 2017 (UTC)[reply]

If I bolt it on without using washers as spacers then the wheel won't turn at all. Mũeller (talk) 09:27, 9 August 2017 (UTC)[reply]

The proper way would be an Axle with grooves for retaining rings at the right positions. If you want to fixate your belt wheel precisely you fix one ball bearing form both without any space for it to move. The other beraring will then only be secured with enough free space so it can run free but not fall off. If precise fixation is not that important you use an Axle with 2 groves and 2 rings that fixates both bearings with enough free space to run properly. You can manage something identical with a screw (put in from the opposite side of your plate, a fitting washer on the side of your bearing to get away from the plate and two nuts where one fixates you first bearing (you will have to get one of them out of your wheel and after reassembling the last nut should be a selfsecuring version at the end of the wheel so it has a tiny space to run free. --Kharon (talk) 10:26, 9 August 2017 (UTC)[reply]

(edit conflict) Those dimensions suggest the use of a ring instead of a machined washer. Try a shop that repairs small electric motors to see whether they have rings of the suitable size. Another approach would be to get a shop to machine a circular groove around the hole in the plate to provide clearance for the outer race, leaving just a small ring around the hole. It's a precision job, needs to be cut only a mm or two deep, and is probably the best solution because it removes the need for a washer or ring which introduce tolerance uncertainties. Akld guy (talk) 10:31, 9 August 2017 (UTC)[reply]

Hang on, your photo had 'standoff' inners on the ball bearings' or am I imagining things (I'm not i just checked)? If not, then yes, you need spacers. Vague badly defined questions get vague answers. Sad but true. Kharon is talking nonsense. Greglocock (talk) 10:35, 9 August 2017 (UTC)[reply]

@Greglocock Well i assume you are a professional (from your page discription). Guess here where i live (Germany) we do construction differently or i wrote it down to complicated. Have a look at the german wiki [9] a glimps on some drawings if you like. Couldnt find any english wiki articles. Because of the many differend bearings, applications and requirements for all possible constructions for all possible tasks the professional approach for bearings ofcourse is much more complicated and sophisticated. --Kharon (talk) 10:57, 9 August 2017 (UTC)[reply]

Yes I am a mechanical engineer. Your post is nonsense in English. Don't blub, i couldn't write a whole sentence in German, never mind using the right technical terminology. Greglocock (talk) 11:14, 9 August 2017 (UTC)[reply]

@Greglocock Nope, unfortunately no standoff or spacers came with the wheels. It's just two standard ball bearings press-fitted inside. The inner race of the bearing stick out maybe 0.2 mm compared to the outer race of the bearing (and the wheel itself) but that's about it.

My question is basically asking where to buy the right spacers. Washers won't work because their OD are too large. I can't find anything COTS that has a ID of 5mm and an OD that's less than 6.3mm. Mũeller (talk) 11:28, 9 August 2017 (UTC)[reply]

Will you consider rubber O-rings in compression? Blooteuth (talk) 13:13, 9 August 2017 (UTC)[reply]

Thanks! I'll give it a try. Mũeller (talk) 13:22, 9 August 2017 (UTC)[reply]

These bad boys may be appropriate http://www.tracgear.com/product/rc4wd/custom/conWasher/dd.jpg or you could try and find the right size of these https://dnwgit7zg7mqr.cloudfront.net/images/141020-UK/800/30475.jpg Greglocock (talk) 16:09, 9 August 2017 (UTC)[reply]

Thanks! Conical washers are exactly what I needed. Much obliged. Mũeller (talk) 02:37, 10 August 2017 (UTC)[reply]

Blindness to important information because of deluge of irrelevant emails

Is there any research suggesting that someone whose received emails are <90% irrelevant to them are liable to start missing information? It happens to me and I'd like to make the suggestion that my college start providing more mailing lists so that people that are meant to be receiving the e-mails do and I and everyone else don't. I imagine that the cost of wasted person-hours is considerable. --129.215.47.59 (talk) 11:22, 9 August 2017 (UTC)[reply]

I would imagine so. If you wanted to start your research in this field, the place to start is Information overload, which is the exact concept you describe, applied to any source of information, not just email. It is a well trodden field of psychology. That article has an entire section on information overload through email. --Jayron 32 11:29, 9 August 2017 (UTC)[reply]

Agreed, it's a real problem. I don't see it as information overload though, because there's no information. It's more of a technical problem (how do I not even see the rubbish), rather than the psychological problem of trying to study a huge table of numbers and extract relevance. The trouble is that it's an arms race - as fast as trimming waste becomes more practical, so does generating more subtle waste that's harder to identify. Andy Dingley (talk) 11:37, 9 August 2017 (UTC)[reply]

If that is the case, then what you're going to have to do is delete the entire section from the Wikipedia article I cited above that specifically discusses how the concept works with email, because according to you the Wikipedia article is wrong and misleading. --Jayron 32 11:58, 9 August 2017 (UTC)[reply]

(EC) This is from a survey by a marketing company so isn't the best quality research and doesn't directly relate to missing information but does suggest when it comes to marketing emails (which I presume aren't what you're referring to), receiving too many or too many irrelevant emails is a common reason for unsubscribing, actually the most common reason of those surveyed. If you look at their report, [10] it's actually also barely the most common reason for marking emails as spam. Nil Einne (talk) 11:39, 9 August 2017 (UTC)[reply]

I'm not referring to marketing emails but e-mails talking about people retiring or meetings that don't even involve anyone in my gosh-darn building or someone selling their ***** sofa (not meant to happen but still does) and so on. There are loads of e-mails intended for specific groups of people but there's no mailing list for them so they just go ahead and e-mail the whole college without even bothering to specify whom they're trying to reach so you're left struggling to determine if and how this e-mail has any relevance to you. — Preceding unsigned comment added by 129.215.47.59 (talk) 14:03, 9 August 2017 (UTC)[reply]

As a practical method I suggest having at least 2 email addresses, one you only give out to trusted parties who won't SPAM you, and another you do give to them, such as when they require an email to join a web site. Read every email carefully under the trusted email address, but just skim the titles under the non-trusted address. To get there from where you are, you might make your current email address the non-trusted one, and send out a new address to those you do trust not to SPAM you. (I'd actually prefer to have a separate email address for each person or business I communicate with, so I can tell who is selling my name, but then I'd need an email system that can collectively view some combo of dozens of email addresses at once, rather than having to log into each individually.) StuRat (talk) 11:55, 9 August 2017 (UTC)[reply]

The questioner specifically mentions college. I have six college email accounts. All of them collect more junk from the college itself than important content. Only one is nice enough to send out a single daily "This is your junk for the day" email. (It is technically called the Campus eConnection.) What I do is use Thunderbird to read all email in one program. That allows me to use Thunderbird's junk email filters to get rid of a lot of the junk. It also allows me to move email from a college account to my personal account if I want to keep track of it better. 209.149.113.5 (talk) 12:13, 9 August 2017 (UTC)[reply]

I wrote a reply here, but decided to move it to Wikipedia:Reference desk/Computing#E-mail deluge instead, as it is more technical, as opposed to the OP's question, which was about the psychological effects of the deluge. — Sebastian 12:43, 9 August 2017 (UTC)[reply]

Antibiotic resistance by production of beta-lactamase

I read a bit about antibiotic resistance and beta-lactamase and I wonder how much antibiotic could be inactivated by bacteria which produce beta-lactam. I guess the rates vary a lot between different bacteria strains and antibiotics and they will probably depend on thousands of conditions. I would be happy with examples just to get an idea of the order of magnitude. --134.76.38.158 (talk) 18:36, 9 August 2017 (UTC)[reply]

It varies enormously. In some bacteria the minimal inhibitory concentrations (MIC) of antibiotics are only modestly increased while other bacteria may become absolutely resistant at least for any concentration that is safe for humans. As an example you can look at Neisseria gonorrhoeae which in 1940s had MIC for penicillin less than 0.05 μg/mL but in 1970s acquired a couple of plasmids and become virtually untreatable with penicillin. Ruslik_Zero 20:55, 9 August 2017 (UTC)[reply]

Which Gazelle species is this article referring to?

This article talks about the "Acacia gazelle", but I can't figure out which species it's referring to - there are lots of gazelles, and none of the ones I saw seemed to match the range and population the article describes. Ariel. (talk) 20:58, 9 August 2017 (UTC)[reply]

It is referring to Gazella arabica acacia, a subspecies of the Arabian gazelle (Gazella arabica) found in Israel. Some theories say that it is going through a speciation process and will eventually become a distinct species. You can read further about it in the article "Wild Gazelles of the Southern Levant: Genetic Profiling Defines New Conservation Priorities". --SuperJew (talk) 22:21, 9 August 2017 (UTC)[reply]

August 10

Rapid spiderling growth

A few weeks I noticed a female Daddy longlegs (mommy longlegs?) with an egg sack in the corner of my bathroom. Now, normally any spider is gross enough to get an eviction, promise of yet more spiders most assuredly included. But this particular spider had only five legs and I figured she'd earned a rest, so I left her alone. About a week ago, the eggs hatched. At first they were so small it was difficult to make out their indivual legs with the naked eye, but just one week later, they have almost tripled in size. And yet, no immediately obvious prey or other source of nourishment. So my question is this: where is all of this mass coming from? Are the babies born with metabolic reserves in a more compact form, which energy they can tap to quickly develope? Or does the mother provide some kind of nourishment? Spider says mothers in some species will regurgitate food for young, but it is unclear if they only do this with recently caught prey; there has been no immediately obvious prey of any size in or below the web, but I can't rule out a quick snack has been missed. Thoughts? 2001:4B98:DC0:47:216:3EFF:FE3D:888C (talk) 12:03, 10 August 2017 (UTC)[reply]

Only 2 cents thoughts. The most simple is usually the better: they eat prey according to their size, that you cannot see (including their own bro, maybe), but you probably thought it yourself already. Also, spiders may eat silk, and things (living or not) that got stuck to it, that may be significant food for a small enough spiderling. And, obviously, most new mass will come from water, considering the water proportion in living being. I hope someone will bring some better answer. Gem fr (talk) 12:33, 10 August 2017 (UTC)[reply]

Prey as small as that are unlikely to be caught in most Pholcidae webs as they do not have strong adhesive quality; their webs are arranged by filaments suspended at every convenient angle, so as to entangle prey, but prey so small as to be tiny compared to even the young spiders described by the OP are unlikely to be caught by such webs. Some spiders do consume their webs, but rarely do they have much nutritional value; more often they do it in order to adjust their nests. I think the OP's original guess is most likely to be right; these spiderlings are probably just developing from their original high-energy reserves. Consider that they do, afterall, develop from embryo to post-embryo (hatchling) without consumption. Also, often the legs of spiders will develop fastest in the first molts; this results in their appearing to grow faster than they in fact are in the aggregate, because the legs, while not a huge additional amount of mass, lead to a significantly larger leg-span and thus perceived diameter.

All of that said, the OP should be on the look out for these spiders to disperse soon. Spiders are highly famine resistant creatures (they are capable of entering into period of highly prolonged and substantial stillness, thus modulating their metabolic rate), but the one exception is early life, for exactly the reasons the OP is noticing here: A) they are developing and burning through their reserve energies and B) they are relatively helpless to collect prey. They make up for this in part by having large numbers of offspring, some of which will be more fortunate than others in securing those early meals, possibly using their mothers nest (though, to my knowledge, Pholcidae do not share captured prey with anyone, not even family), but more likely after securing their own. Cannibalism is also quite common among the young of many species. The Pholcidae family is also known for their willingness to tresspass into the webs of other spiders to steal their food or even kill the inhabitants and/or eat their eggs, so there's that too. Here's some useful additional reading: [11], [12], [13] Snow ^{let's rap} 13:39, 10 August 2017 (UTC)[reply]

Shivering

At what temperature does shivering start at? Assuming wearing light clothes. — Preceding unsigned comment added by 5.200.42.234 (talk) 14:20, 10 August 2017 (UTC)[reply]

It is not a set temperature. Some people lose the shiver response due to age or injury and never shiver. Some people shiver when hot (fever chills). Normal shivers are triggered by core body temperature vs skin/spinal temperatures and vary from person to person. 209.149.113.5 (talk) 15:37, 10 August 2017 (UTC)[reply]

An HVAC book may have that study where they kept people at various temperatures for hours/temperature and I think the average was around 55°F. Sagittarian Milky Way (talk) 16:05, 10 August 2017 (UTC)[reply]

You can train yourself to not shiver and tolerate extreme cold much better, see here, and here, and here. Deep and fast breathing exercises are important if you want to tolerate extreme cold for a long period. In the beginning you'll hyperventilate when doing that, but you then train the body to burn the oxygen and produce more CO2 whenever you start breathing like that, thereby increasing the metabolic rate significantly. This allows you to sit naked in ice cold conditions without shivering, you're breathing faster and burning not the usual 100 Watts but 300 Watts or even more. Count Iblis (talk) 19:47, 10 August 2017 (UTC)[reply]

Shivering can be a response to illness, or to perceived heat-loss through the skin, not just a low core temperature. I have reported before, my father recounts working on a windy day in West Texas in the 60's. The temperature was 70, and being 6'2" and 250 lbs that would be a comfortable day in the Philadelphia shipyards, where he apprenticed. But the humidity was 02% and he started shivering as soon as he got out of the car at the worksite, and had to get a winter coat (to a Philadelphian) to work in outdoors. μηδείς (talk) 01:59, 12 August 2017 (UTC)[reply]

Is there a phobia of being in a building much narrower than it's tall?

Sagittarian Milky Way (talk) 15:34, 10 August 2017 (UTC)[reply]

Nearly every named "phobia" you've ever heard of is a product of folk psychology and is not a recognized mental disorder, as defined by actual psychologists, such as the DSM-5. The only types of phobias widely recognized are social phobia, specific phobia, and agorophobia. There are hundreds of dubious sources that will claim to give faux-Greek names to phobias (like "coulrophobia", fear of clowns) but these are NOT recognized by medical professionals as distinct disorders, instead they are all classified under one of the other phobias. A fear as specific as you name is known as a type of specific phobia. --Jayron 32 16:04, 10 August 2017 (UTC)[reply]

One of Steven Wright's early jokes was, "I was out walking my dog today... on the ledge. Some people are afraid heights. I'm afraid of widths." ←Baseball Bugs ^{What's up, Doc?} carrots→ 21:37, 10 August 2017 (UTC)[reply]

Mother of all arachnophobia

Recently I was reading a funny story about arachnophobia - a woman on a field expedition was climbing a steep hillside and abruptly backpedalled, frantic, finally yelling a distressed cry of "Sp-i-i-i-der!" And yet --- it turned out her fear was entirely justified, because the story occurred in Australia. Unlike in the U.S., where arachnophobia is a joke, almost seen as a psychiatric ailment, everything in Australia is apparently out to kill a person with poison. Which got me to thinking...

I have read that other primates have specific distress calls for poisonous spiders. Obviously any spiders of relevance would have had to be encountered by human ancestors in Africa. So ... is it possible to identify the one and only specific kind of spider, against which all human arachnophobia is directed? Is this thing perhaps more inherently terrifying than any other kind of spider, things that merely resemble it?

Starting with such ahem reliable sources as [14], I am directed in the direction of button spiders. There are images like at the top of this article which suggest that oh my, that is one scary looking spider. But can someone here do better, provide some compelling context that makes it out as the definite culprit, or proposes alternative suspects? Wnt (talk) 20:31, 10 August 2017 (UTC)[reply]

Deaths or serious injuries from spider bites are very rare even for mentioned black widow spiders. So, this can not explain arachnophobia. Ruslik_Zero 20:57, 10 August 2017 (UTC)[reply]

It still probably hurts like hell right? The level of medical technology for most of this subspecies' existence was something like drill a hole in the skull or add leeches. Spider deaths must've been more common then. Sagittarian Milky Way (talk) 22:41, 10 August 2017 (UTC)[reply]

I'm assuming that the evolution (or retention) of such an instinct would occur over millions of years. Homo habilis and Australopithecus spp. were generally shorter than modern humans from Homo ergaster on, less than 4 feet I think. I don't know if overall smaller brains would make them more susceptible to a neurotoxin than other humans with the same body mass but larger brains. I should admit that I am susceptible to a crank variant of the old (discredited) aquatic ape hypothesis, in that I am suspicious that human ancestors developed elongated feet and bipedality and fire use in West Africa, in the Okavango delta or nearby (formerly wet) terrain with regular flooding and wildfires; if this is true, then suggesting a black button spider (Latrodectus indistinctus) with the strongest toxin which lives north into Namibia is acceptable - but otherwise (where the known fossils are in East Africa) there could be a problem with the range. This spider (or our closely related black widow) seem like decent options for being 'instinctively' disturbing, but I'm not sure the black button spider is archetypal. Wnt (talk) 01:22, 11 August 2017 (UTC)[reply]

Not necessarily answering, but just linking to signalling theory and aposematism, which are somewhat on topic and interesting. —Paleo Neonate – 00:55, 11 August 2017 (UTC)[reply]

I just cannot believe that spiders were ever enough a threat to trigger an evolutionary adaptation, and turn arachnophobia into a competitive advantage. As opposed, for instance, to "mosquitophobia" (red link !), THIS would had been, and still be, a real competitive advantage, but doesn't seem very common (if it ever exist).

fear is known to be triggered, among other things, by startling quick movement of the thing; mice and spiders are both capable of this kind of movement: they just stand still, then they surprisingly dart or even jump (Salticidae) in any direction, including yours, and THIS is indeed threatening (even though you may laugh afterward of fearing such a small thing). On the other hand, when you learn (from experience, not from books), that Pholcidae do not move this scary way, you stop finding them scary.

Plus, spiders and their webs are also a thing that will surprise you in scary environments, such like caves, dark wood, or darkness of the night, and trigger Startle response (who here didn't startle when feeling a spiderweb on his face in a wood or a cellar?).

So, for my 2 cents, the simplest explanation of arachnophobia do not involve any genetic memory of any spider of the past, but rather natural association of spiders with fears: surprise movement, and fearful environments (darkness, enclosed space,...)

Gem fr (talk) 09:15, 11 August 2017 (UTC)[reply]

Interesting! Might this also be the cause of mottaphobia, given that butterflies also tend to make surprise movements, and some (like the Monarch) are also quite large? 2601:646:8E01:7E0B:21B1:8CA4:6F9F:6132 (talk) 08:33, 12 August 2017 (UTC)[reply]

We certainly do have "mosquitophobia", though it is more like "Islamophobia" in terms of the specific emotions involved. The whine of mosquitoes is uniquely annoying (well, maybe not uniquely given that flies have also been made annoying, but it is at least distinctively annoying), their bite distressing, the impulse to swat them universal. The number of mosquitoes is a critical factor that forces participants in survival shows to camp one place rather than another, more than access to food and water. But ... swatting spiders may not work like swatting mosquitoes, and unlike mosquitoes, spiders are readily avoided if one has the right emotions. Given that the bite of a button spider is regarded as a medical emergency according to our article (even though Lonely Planet assures folks button spiders are "harmless"...) I continue to think it is plausible they could arouse this reaction. Wnt (talk) 12:26, 11 August 2017 (UTC)[reply]

Formula for walking on gradients

If I burn, say, 100 calories by walking a certain distance on a flat road (0% gradient), is there any formula that allows me to calculate how many calories I would've burnt by walking the exact same distance but on a 5% uphill gradient? --90.69.12.160 (talk) 22:20, 10 August 2017 (UTC)[reply]

Find a formula for climbing, multiply your walking distance with 0.05 (5%) and use it as climbing distance and then just sum up both results. --Kharon (talk) 23:09, 10 August 2017 (UTC)[reply]

This paper looked at that question: http://jap.physiology.org/content/93/3/1039.full the study was conducted on treadmills. The metabolic cost of walking (Cw) in J/(Kg *m) was empirically determined to be 280.5i⁵-58.7i⁴-76.8i³+51.9i²+19.6i+2.5 where i is the incline.208.90.213.186 (talk) 23:14, 10 August 2017 (UTC)[reply]

incline in %?

practitioners of hiking in hill/mountains have a rule of thumb: 100 m up is equal to 1 km, as efforts go. Meaning a a 10% uphill gradient doubles the distance, and 5% increase it by 1.5.

note that this rule of thumb is pretty well in agreement with the study mentioned by 208.90.213.186, provided i is indeed in %

Gem fr (talk) 09:30, 11 August 2017 (UTC)[reply]

For time required to walk a certain distance factoring-in gradients and terrain, see Naismith's rule. Alansplodge (talk) 12:26, 11 August 2017 (UTC)[reply]

August 11

Why do vanilla ice cream manufacturers have to color the vanilla ice cream?

I think vanilla ice cream is supposed to be white. I made vanilla ice cream in chemistry classes, using two methods. One method was to lower the temperature of the ice in the plastic bag with salt by shaking. Another method was to use liquid nitrogen on the cream. The only ingredients used were half and half cream and vanilla extract. The finished result looked white. Why can't ice cream manufacturers just make the ice cream look white? Why do they add annatto for color? 50.4.236.254 (talk) 01:46, 11 August 2017 (UTC)[reply]

Because pure white is a very fragile tone, set off by the tiniest portion of a color, like in Aquarelle starting on a clean white paper. In contrast adding very cheap beta-Carotene for color causes an orange tone which is most appealing and a very good disguise especially for tone setoff's naturally caused by aging (Rancidification) which also usually causes an orange tone. --Kharon (talk) 02:46, 11 August 2017 (UTC)[reply]

Milk looks white. Ice cream is derived from milk. So, why is it cheaper to add a color than to keep it the way it is? 50.4.236.254 (talk) 03:10, 11 August 2017 (UTC)[reply]

Its not cheaper than not adding anything ofcourse but beta-Carotene is very cheap and very little of it is needed to get the orange on top. They simply dont want to sell white ice cream for multiple reasons and add beta-Carotene for multiple reasons. You cant make ice cream more appealing and cheap any other way. --Kharon (talk) 03:34, 11 August 2017 (UTC)[reply]

Note: Real vanilla isn't white, but is rarely used in common ice-cream today, to reduce production costs (more than retail cost). Likewise, real cream is only used in the costly brands, but was also traditionally off-white. If the goal was to make the icecream very white, there would be other options like titanium dioxide. —Paleo Neonate – 03:39, 11 August 2017 (UTC)[reply]

What do you mean by "costly brands" and "real cream"? In NZ, Tip Top (ice cream) the retail price where I live in Auckland for a 2L tub of ice cream tends to be $4.50-5.50 although occasionally is available for $4. This would be considered by most to be ordinary ice cream, not the real premium or fancy ones which come in smaller containers and tend to be twice as much or more per L. It's also sold as ice cream meaning it I presume meets the legal requirement of [15] "consisting of not less than 100g/kg of milk fat". (Tip Top also has 55% of the market share in NZ [16], not just from their tubs of course.) By comparison, Much Moore (formerly Kiwi) Marvels brand products are generally $3.80-$4.50 for 2L. Some products under their Marvels brand are ice cream, some are frozen dessert (i.e. either don't have any cream, or don't have enough to meet the legal requirement to be called ice cream in NZ/Australia). Some cheaper products which are I believe all frozen dessert are generally $3.29-$3.79. The Much Moore 'premium' range, which is still just sold in a normal 2L tub is generally $4.30-$5 (sometimes, more often than Tip Top $4) and I believe is all ice cream. Other products tend to be similar price ranges and many of them are ice creams. Admittedly not all ice creams use something which may be called cream in their production, e.g. I believe the Much Moore Marvels range uses milk solids but the point remains most or all of the fat is milk fat. In any case, Tip Top ones do say they use cream e.g. [17]. Some may also use thickeners for various reasons. Nil Einne (talk) 07:28, 11 August 2017 (UTC)[reply]

Forgot to mention that Tip Top is of course nowadays owned by Fonterra Co-operative Group one of the largest dairy countries in the world (and who by their dairy coop nature are mostly focused in dairy products, unlike say Nestlé which is a general food and beverage company, or likewise Danone) , so it's not particularly surprisingly they generally use cream or otherwise use milk fat. Nil Einne (talk) 15:30, 12 August 2017 (UTC)[reply]

Most of the vanilla ice cream I've seen is cream-colored, which is to say very pale yellow. On occasion I have seen the heavy yellow vanilla, which is associated here with cheap store brands. Is the yellow ice cream you guys get the norm outside the US? Abductive (reasoning) 06:23, 12 August 2017 (UTC)[reply]
- Vanilla is cream-coloured; that is, it's not pure white. I wouldn't refer to it as yellow. Maybe you're confusing it with the unique NZ variety of ice cream called hokey pokey. Akld guy (talk) 09:26, 12 August 2017 (UTC)[reply]

Note that French vanilla ice cream adds egg yolks, making it more yellow: [18]. This is considered a premium version, so it's not surprising cheaper vanilla ice creams may be made to imitate it. StuRat (talk) 16:16, 12 August 2017 (UTC)[reply]

Vanilla ice cream is generally yellowish in the UK. Only the very cheap stuff is white. Wall's Ice Cream is probably the market leader here; it lists "Colours (Annatto, Curcumin)" amongst the ingredients, but no actual vanilla. Alansplodge (talk) 17:22, 12 August 2017 (UTC)[reply]

Interesting. There seems to be regional variations. Abductive (reasoning) 18:54, 12 August 2017 (UTC)[reply]

Metabolism of high-fiber food

I don't understand how dietary fiber affects metabolism and how it affects the stated calories in package labeling in the US.. Consider a bean dish (Gefen Cholent Mix) in which one portion is supposed to provide 70 kilocalories of energy, with 0 fat, 23 grams of carbohydrate, which includes 13 grams of dietary fiber, and 8 grams of protein, per the package's nutritional label. Each gram of carbohydrate should provide 4 kilocalories, as should each gram of protein. The 31 grams of combined carb and protein should provide 124 kilocalories rather than the stated 70 kilocalories. If the 13 grams of fiber (presumably not metabolized by humans) are deducted from the 23 grams of carb, then there would be 18 *4=72 kilocalories of energy per serving., 3% more than the stated amount. Would 23 grams of carbohydrate be converted into glucose in the bloodstream. or would only 10 grams of carbohydrate be converted into glucose? This would seem to be a big deal vis a vis the amount of glucose which enters the bloodstream after such a high fiber meal. Edison (talk) 03:52, 11 August 2017 (UTC)[reply]

That's presumably because, as stated in Food energy#Nutrition labels, energy is estimated, and obviously the labeling authorities do not care for few % difference, as they themselves use an official table were, for foodstuff, 4 cal = 17 kJ instead of 16.736 kJ that a physicist would use, that's a 1.5% difference. Add some rounding issues and tolerated variations in content: things will quickly add up to 3% difference you noticed.

Gem fr (talk) 10:05, 11 August 2017 (UTC)[reply]

Calories are generally rounded off to the nearest 5 Calories (kcal), which means that for any food greater than 60 Calories (kcal) the 3% would be statistically insignificant, as it would have been rounded off. In the example above, 2 kcal is within the rounding, so it was just rounded off. Statistically speaking 72 and 70 are identical when you're rounding to the nearest 5. --Jayron 32 14:50, 11 August 2017 (UTC)[reply]

Fiber is metabolized by humans, the USDA gives a value of 2 kcal per gram. Abductive (reasoning) 06:25, 12 August 2017 (UTC)[reply]

That depends on if it's soluble fiber or insoluble fiber. StuRat (talk) 16:20, 12 August 2017 (UTC)[reply]

Presumably the 2 kcal/g is an average...Abductive (reasoning) 18:52, 12 August 2017 (UTC)[reply]

Hmmm, the wiki article says that what matters is whether the fibers are broken down by bacteria and then absorbed by the body, the energy content is then attributed to whatever the body will absorb and metabolize. However, the breakdown of fibers in the gut also releases energy and this is not accounted for at all. Count Iblis (talk) 19:29, 12 August 2017 (UTC)[reply]

Eat fewer Calories to lose the weight or eat the same amount or greater Calories to build muscle and thus increase metabolism?

On one hand, people recommend to the general public to eat less. On the other hand, athletes are recommended to eat more to complement the intensive physical activities. Okay, what happens if an overweight person doesn't want to lose weight so he eats the same amount of food (or more, not less) and adds an intensive strength-training and aerobic exercise (such as doing push ups and running) to nourish muscle growth? 140.254.70.33 (talk) 16:32, 11 August 2017 (UTC)[reply]

He has better health outcomes. Well, possibly not him, because of individual variability, but if you got some statistically large enough sample of such people, a significant portion of them would have a better quality of life.[19] --Jayron 32 17:38, 11 August 2017 (UTC)[reply]

You have to note here that being able to burn a significant additional amount of calories compared to the total calorie intake requires being very fit to begin with. E.g. a 60 kg man running fast for an hour will burn roughly 1000 Kcal more due to this exercise. But you won't be able to do this unless you have excellent cardio fitness. Strength training burns only a small amount of energy. That's why body-builders do some cardio training besides the massive amount of strength training. Count Iblis (talk) 17:58, 11 August 2017 (UTC)[reply]

A doctor I do research with began his research with an interest in football and studied obese linemen. They are clearly obese, yet they exercise extensively. So, are they healthy? No. Obese NFL players tend to have cardiometabolic syndrome. After retirement, that quickly leads to hypertension, diabetes, and hyperlipidemia, all of which quickly lead to life-ending problems such as congestive heart failure or renal disease. There is a lot (more than you'd think) research on obesity in the NFL, which gets right to the issue of obesity and exercise. Check scholar.google.com. 209.149.113.5 (talk) 19:31, 11 August 2017 (UTC)[reply]

I would say that they were not obese when they were athletes, as then the weight was mostly muscle. But, yes, ex-athletes do tend to continue to eat as much, but get less exercise, turning that muscle into fat, at which point they become obese.

As for them being "clearly obese", that sounds like you are only looking at weight, not muscle and fat percentages, although there are some "athletes", like sumo wrestlers, who really are obese. StuRat (talk) 21:55, 11 August 2017 (UTC)[reply]

Indeed. Count Iblis (talk) 23:37, 11 August 2017 (UTC)[reply]

It is preseason. Watch an NFL game. That flab on the linemen is not muscle. It is fat. They are obese. 71.85.51.150 (talk) 00:40, 12 August 2017 (UTC)[reply]

Yes, it is possible that they get "out of shape" between seasons, then "shape up" at the start of the next season. One problem with massive muscles is they take massive exercise just to maintain. Otherwise, they are replaced by fat. StuRat (talk) 01:05, 12 August 2017 (UTC)[reply]

As far as I can tell, the 71 IP is not suggesting that linemen have fat not muscle only preseason. I'm not sure why they mentioned preseason but I think they're suggesting perhaps people have forgotten what linemen look like since it's preseason so they should go back to a (non preseason) NFL game. Even if the IP was suggesting that the flab on linemen was fat and not muscle only during pre season, I seem no reason to think that is correct.

I'm under the impression the NFL is a professional sport where atheletes are often paid multimillion dollar salaries. I'm not sure if those salary ranges apply to linemen but at a minimum I'm assuming their positions are still highly competitive. In general, while professional athletes may lose a bit of fitness during the early parts of an offseason, they can't afford to let themselves go as badly as you suggest because they won't be able to recover in time for the season and will find themselves not very popular with the people who can significantly affect their careers like coaches.

According to [20]/[21]/[22]/[23] the average body fat percentage for offensive and defensive linemen was 24.8%. Okay this is for high school and NCAA football players and was during an off-season training season and high school was 26.1% and college was 22.9%. However none of the authors expressed any concerns these players had really let themselves go so they weren't looking at a good sample. (I'd also note that when in the off-season is unspecified. Even if you believe that athletes can get very bad during the first month or so of the off-season, you've surely, I hope, got to realise a month before the season starts athletes need to be close to their peak condition.)

This [24]/[25]/[26] looked at NFL players and suggests offensive line has an average body fat percentage 25.1%. It also says:

The only exception was observed with the offensive line, where values for BMI were higher, accompanied with the classification of ‘‘poor’’ in health estimation, but the %body fat still did not represent extreme values as noted by the BMI.

The extreme here is likely referring to the fact that BMI show them to severely obese category but clearly whether you want to call them obese or not their body fat percentage has reached levels not considered healthy in the general case. Again this was during a summer training camp, prior to the start of the season. I'm not sure how far away the season was, but the authors seem to have similar thoughts to mine:

As such, we felt that each player would be in top condition after an off-season conditioning program and summer minicamps.

Next there's [27] which has results for the 2006 – 2013 NFL Combine testing using Bod Pod and gives 24.6% average body fat for offensive line. Admitedly I'm confused what the source for these figures actually is since that says it's from “Current Assessment of Body Composition in Sport” but I can't find that source. Other places says it's in Sports Med 42(3) but the closests thing there is [28]/[29] "Current Status of Body Composition Assessment in Sport". Anyway I would guess it's just a typo or maybe the title was renamed after pre-release. But more importantly, AFAICT that source doesn't have such figures nor does it have any additional data. And considering it was published in 2012 it would seem weird for it to have 2013 figures. Still the BodPod is definitely used as part of the combine [30] so probably they are somewhere.

Anyway assuming we can trust in-thinair.com to accurately report the figures, wherever they were published, I presume this means the NFL Scouting Combine so technically this is off season too. But considering what the NFL Scouting Combine is for....

Either the athletes go 'you know what, the combine is coming up but I don't have to be in peak condition because it's offseason so let's not worry that this moment could make or break my life and if I was only able to keep it I'll be much more impressive since after all at least the next dude will have the same attitude as me so while I may not be better than them even though I could be, I won't be worse'. And the coaches, scouts etc say 'hey that guy is fat, but I'm sure he just let himself go in the offseason and will regain it over the next few months, let's not worry about our experience or the whole purpose of this combine; you know as that person on the RDS said, it's normal for people to let themselves go so badly out of season.'

Or these people are in top condition for assessment during the combine. (Of course it's possible that being fat is seen as impressive by observers during the combine, but is actually bad while playing but this seems to make further weird assumptions.)

Nil Einne (talk) 06:30, 12 August 2017 (UTC)[reply]

BTW, I noticed [31] in my research but it doesn't directly relate to the body fat percentage issue although I just noticed it does mention an absolute weight limit at college level which may affect the earlier figures. Looking a bit more it seems that the size of linemen is a concern in both American [32] and Canadian [33] football. I'd note that the middle source claims as those the earlier links, as well as the middle source just now both claim the linemen size has significant increased over the past few decades. Although interesting [34] it could be going down again, for reasons unrelated to health concerns. Also about Bod Pod and similar measurements, I should mention that one thing the Sports Med source does say backed by an RS is is that such devices tend to underestimate body fat for college football players (I assume this is American, or maybe Canadian since I don't think anywhere else would refer to college football players) by an average of 2%. So assuming the above figures are unadjusted, they may be a little on the low side. Although an average of 2% needs to be taken with caution if we're talking about people with fairly different body types depending on their precise position, which the differing body fat percentages suggest is the case. 07:05, 12 August 2017 (UTC)

Maintaining that level of muscle mass during the off-season would require that they exercise just as much as they do during the regular season, which is basically a full-time job. So, it's not exactly being lazy to not keep up. Do you do the same amount of work when on vacation as when at work ? StuRat (talk) 16:26, 12 August 2017 (UTC)[reply]

I mentioned that it was the preseason to indicate that it is very easy to find a video or even a photo of an NFL lineman right now. Look at Dontari Poe. There is a photo of him, during the season, when he is "in shape" right on the page. Look at his lower abdomen. That is not muscle bulging out. That is fat. Yes, he does have a lot of muscle. He also has a lot of abdominal fat. That is the norm for linemen. They have a lot of abdominal fat. You have to be very stubbornly ignorant to look at the photo of Dontari Poe and think that his spare tire is all made of muscle. I would like to have more examples right here on Wikipedia, but I've noticed that there is a distinct lack of uniform photos for linemen. I checked Albert Haynesworth, Jerome Bettis, Dan Wilkinson, etc... I didn't even go after other positions, such as Jared Lorenzen, who I believe is the most obese quarterback ever signed in the NFL. I feel that only someone who has never watched an NFL game can claim that linemen are not obese. However you want to measure obesity, when your belly is hanging inches over your belt, that is fat, not muscle. I'm not saying it to fat shame. I am trying to point out that those players are exercising daily. They are athletic. They have a lot of muscle. But, they are still obese and they still have obesity-related diseases. 71.85.51.150 (talk) 18:41, 12 August 2017 (UTC)[reply]

They exercise, but not like this. Count Iblis (talk) 18:50, 12 August 2017 (UTC)[reply]

See an endocrinologist who specializes in weight loss/body mass index. There are various metabolic disorders as 209 noted that you cannot self diagnose, and we certainly cannot diagnose. He can recommend a nutritionist and medication. Then folow his advice on exercise, under a licensed trainer. Don't ask for medical advice here. μηδείς (talk) 21:47, 11 August 2017 (UTC)[reply]

Is any new research still done with optical microscopes?

If not, what was the last time it was? Sagittarian Milky Way (talk) 17:26, 11 August 2017 (UTC)[reply]

This very day, I'm quite sure my wife used one. She's a forensic scientist who does microscopy as a daily part of her job. She uses a regular old, binocular optical microscope fitted with a camera to record what she sees for evidence. The McCrone Research Institute is probably one of the major players in microscopy in the U.S., and still does work with all sorts of work with light microscopy. So the last time they did active research in the field is quite likely right now. --Jayron 32 17:35, 11 August 2017 (UTC)[reply]

Probably 95% or research in medicine, biology. geology, etc is done with optical microscopes. --AboutFace 22 (talk) 19:19, 11 August 2017 (UTC)[reply]

They certainly are important, but that number is too high for medicine. Don't forget about the vast amounts of work done with molecular biology techniques, and things like Western blots, flow cytometry etc etc. I know a fair few people in neuroscience who never get near a microscope. They are a minority, for sure, but they are more than 5%. Even I, a regular microscope user in neuroscience, don't do 95% of my research on them, I do too many qPCRs for that! Fgf10 (talk) 23:46, 11 August 2017 (UTC)[reply]

We used light microscopes daily in my old lab, for everything from insect ID to counting pollen. I think maybe you are undervaluing how useful it is to see little things across many, many fields of inquiry. Nobody in my old lab ever published new research specifically about a new thing that they found with a light microscope, but they certainly published new research that could not have been done without a microscope.

If you want an example of new things recently discovered with a light microscope, check out this [35] coverage of a 2013 Science paper about naturally occurring gearing mechanisms. Sure, the press photo is from an electron scope, but that's just because it is easier to see, looks cool and they had the money to do it. These features are visible under relatively low power, as shown by the video at that link, which is just a normal light scope. This is top-notch, ground-breaking research that basically amounts to "We looked at this small thing with a light microscope and found something really cool that we think all scientists should know about."

TL;DR: yes, lots of research is done every day with light microscopes, probably thousands of people are doing it as I type.SemanticMantis (talk) 19:41, 11 August 2017 (UTC)[reply]

I think you meant to link here : [36]

Very cool. ApLundell (talk) 22:55, 11 August 2017 (UTC)[reply]

You are mistaken if you think that the light microscopy is some old and stagnant technology that has not changed for a long time. On the contrary new optical methods are actively being developed. Moreover some of them like the fluorescent microscopy earned their creators a Nobel prize. Ruslik_Zero 20:00, 11 August 2017 (UTC)[reply]

You'll have to specify which optical microscope. In my neuroscience research, I use both phase contrast and epifluorescent optical microscopes essentially every day. I frequently use dissection microscopes, and pretty regularly use a confocal fluorescent microscope or two-photon microscope. Conventional bright field microscopy is not used much in my field, but certainly is in others. Take away my optical microscopes and 90% of my research is gone. Fgf10 (talk) 23:43, 11 August 2017 (UTC)[reply]

No one has mentioned that many a biological sample would be destroyed or ruined if they were prepared and placed in the vacuum of an electron microscope. Also, did Nikolaus Pevsner have to examine every brick? One uses the right tools for the job. Aspro (talk) 01:00, 13 August 2017 (UTC)[reply]

August 12

Finding out the Map Projection

Which map projection is used at this map of the European Inland Waterway Network?

--Baltimax (talk) 01:09, 12 August 2017 (UTC)[reply]

Albers projection. Barely visible Latitude lines are round instead of the straight ones resulting in Mercator projections.--Kharon (talk) 03:19, 12 August 2017 (UTC)[reply]

How are you so sure it's Albers? Hundreds of projections have round or at least curved lines of latitude (and many other than Mercator have straight lines). 78.234.66.210 (talk) 17:49, 12 August 2017 (UTC)[reply]

Yes, see Map projection#Conic. But I don't think it's any conic projection as defined on that page. If you zoom in, particularly on the right-hand side where the longitude lines are farthest from vertical, and look carefully, you can see that when they cross the latitude lines they aren't exactly perpendicular. Really the best way to get a reliable answer would be to contact the UNECE office that issued the map and ask them. --69.159.60.147 (talk) 19:58, 12 August 2017 (UTC)[reply]

Language loss

How fast can one lose a language? Back when I was in high school, I learned that Native Americans were forced to assimilate into White-American society. The teacher said that if one can't practice one's own language, then one can lose it in a few months. I personally started learning Spanish in 7th grade and moved all the way up to 12th grade and took two courses in college to fulfill a general education requirement. After the two classes, I hardly practiced Spanish, and somehow I still can remember Spanish words and the Spanish songs stuck in my head. SpanishDict may have a random word of the day, and somehow I'd know them. How is this possible? 50.4.236.254 (talk) 04:16, 12 August 2017 (UTC)[reply]

"A few months" is absurdly quick. You might get "rusty", but after returning to people speaking that language you would recall it quickly. However, the age of the person does matter. If you cut very young children off from their native language before it "sets", then they might indeed forget it. StuRat (talk) 04:19, 12 August 2017 (UTC)[reply]

Agree with Stu. It is more a case of falling out of the 'habit' of using ones native tongue. There are plenty of anecdotal occurrences of people who fled as refugees to America during War II who thought they had forgotten their mother's tongue only to find during a visit to their homeland (after the fall of the Soviet Union and the reunification of Germany when travel there became easier) it took only two weeks to be talking fluently once more in the language they thought they had long forgotten. The mind is quite plastic at taking off line any memory banks that are currently not required and bring them back online again when circumstances change. Entheogenist find one of the characteristics of drugs like LSD and Ketamine is that they appear to bring all memory banks online -all at once. Yet, after daily doses, the mind adapts (is plastic) and takes them off line again and further dosses have no longer any psychedelic effect. This goes for physical skills as well. One may have not played a piano for many decades but with a little practice it all come back again. Even on those instruments that don't require depressing a key to hit a felt hammer onto strings stretched on a iron frame, in a wooden enclosure , which is all we had before MIDI. And we could still play them during a brownout or complete cut ! Aspro (talk) 10:44, 12 August 2017 (UTC)[reply]

Or the classic case of riding a bicycle, which comes back to you after years of not riding. StuRat (talk) 12:55, 12 August 2017 (UTC)[reply]

To echo Aspro, I spoke Spanish to age four, along with my native English, since my parents both got by in it and we lived in Puerto Rico where I had a monolingual Spanish-speaking nanny and Texas, where my best friend was Mexican. When I was four-and-a-half, we moved to a town in NJ where the population were all third generation or more Europeans (mostly Irish and Italian) and I got odd looks and no response when I spoke Spanish to people, which led to a few teary incidents. I subsequently "lost" it.

When I was 18, I worked in a kitchen with Filipinos and Mexicans as I went to college. I told them to address me only in Spanish. With the help of 201 Spanish Verbs and my HS French I was basically fluent again in non-literary level Spanish within a few months, to the point of dreaming in it, and finding myself at a loss for an English word on a few occasions. μηδείς (talk) 16:52, 12 August 2017 (UTC)[reply]

That's interesting. My first language was Chinese, I spoke it till I was four and since then have only spoken English. I don't even remember ever having spoken Chinese, it would be interesting to try and learn it again. Dmcq (talk) 17:11, 12 August 2017 (UTC)[reply]

So it appear that the OP's teacher was just over simplifying things. Was interesting that μηδείς found herself lost for words at times. Think this was not so much 'words' as phrases. The ancient Greek's had a lovely phase that translates into English simply as potter against potter which referred to arguments that arise between two experts who both insist they are right – there is no English equivalent to express that. Also some of the French double negatives such as Je t'aime... moi non plus defeats my ability to translate in real-time. @ User talk:Dmcq. The big problem foreigners have, with learning Chines, is to developer an ear to for the tonal syllables in order to differentiate meaning. If you also have some musical training then getting up-to-speed again in Chines may be even an easier endeavour. Don't expect results over night but if that tonal pattern is still there in your brain’s neural network, then it will be easer to relearn. Aspro (talk) 18:22, 12 August 2017 (UTC)[reply]

Just googled this about Chinese: Mandarin Chinese is a tonal language. Also, children who have a tonal language are also better at being pitch perfect when they become musicians like Vanessa-Mae. Aspro (talk) 19:23, 12 August 2017 (UTC)[reply]

Well I still have people wondering what my accent is and where I come from so perhaps the ear is still there too :) Dmcq (talk) 21:50, 12 August 2017 (UTC)[reply]

I wonder if people who are tone deaf have difficulty speaking Chinese. StuRat (talk) 18:54, 12 August 2017 (UTC)[reply]

Good question. They might be viewed upon in the same way that ~~dislektiks~~ ~~dieslettics~~ ~~dyslolectics~~ dyslexic's are treated in the west. We need an academic of tonal languages to comment on this. Even dyslexic's who have trouble with the written words have trouble sometimes with pronouncing words ~~write~~ right. Yet, mother nature appears to endows them with other gifts. Albert Einstein was a rotten speller in both German and English and history is littered with dyslexics who became very influential. With tonal languages it can get even funnier. Example: truck driver arrives to deliver his load. It can come out sounding “I am about to give birth”. Aspro (talk) 20:08, 12 August 2017 (UTC)[reply]

Ah yes, the Wide Berth of a Nation. :-) StuRat (talk) 20:37, 12 August 2017 (UTC) [reply]

What's called tone in tonal languages is not the same as the musical pitch of notes on a tuned instrument; it's about contour. We have this in English, but use it on a sentencial level, with normal declarations having a falling intonation, questions a rising intonation: "The book he wants is _here.." (fact) vs. "The book he wants is ^here?" (question). The word "really" Can have many different intonations:

Really? Really.

Really?!?! (doubt). Really! (exasperation) Really... (sarcasm).

These are all a matter of contour, not pitch. And notice that we do not mistake a woman's statement for a man's question just because her voice is higher pitched. μηδείς (talk) 20:44, 12 August 2017 (UTC)[reply]

That reminds me of the time when I was studying Russian at university. One day during a tutorial, the tutor was asking us to translate English sentences into Russian, viva voce. The sentence I was given was "One day I would like to marry and have a couple of children". I said whatever rubbish I said, and both the tutor and a fellow student who was a native Ukrainian speaker and understood far more Russian than I, suddenly erupted into gales of laughter. They explained that I had said the Russian for "One day I would like to give birth to twins". :) But seriously, that was 3 years of pretty intensive Russian study in the late 1970s-early 80s, followed by only very sporadic use of the language thereafter (including having never been to Russia; although I did marry into a Russian-speaking family). To this day my Russian pronunciation is still fine, but I have lost a lot of vocabulary, and I never really did get verbs of motion (mainly because we were warned before we started learning them that they were difficult and some learners never understand them, so as a dutiful student I complied, which is a pity because in most ways I rebel and do the thing I am not expected to do). -- Jack of Oz ^{[pleasantries]} 20:36, 12 August 2017 (UTC)[reply]

@ Jack of Oz. As you spent so much time in learning this language why waist all that that effort. You might not know it but that there is a web-site called Википедия whom might welcome your input and thus you can improve your vocabulary. But be warned and take it from me, this is part of a org that insists that one follows unfathomable policies about what images and references one can use. No idea how this world wide international organization still exists (they don't pay their contributors anything). Yet, give it a try ;¬ ) Aspro (talk) 22:49, 12 August 2017 (UTC)[reply]

Ну, спасибо ... я думаю ... :) -- Jack of Oz ^{[pleasantries]}

спасибо Aspro (talk) 01:55, 13 August 2017 (UTC)[reply]

Dmcq may find Mango Languages, a service available at my public library and may be available in his/hers, and HelloTalk, a chat app for Apple products, to learn new languages. Mango Languages may not be very useful, because it has preset sentences that require memorization and repetition. But HelloTalk may be more useful, because it is designed as a language-learning social app. The app will ask Dmcq to create a profile and set up a native language and learning language. If he/she wishes to learn Chinese, then s/he may speak with a person from China who is trying to learn English. 50.4.236.254 (talk) 22:10, 12 August 2017 (UTC)[reply]

I once worked with someone from a European country who was stationed in the US for a year. As the end of the year approached, he said he was "starting to" forget some of his native language. It all came back once he went back home and was re-immersed in it. ←Baseball Bugs ^{What's up, Doc?} carrots→ 17:14, 12 August 2017 (UTC)[reply]

@Dmcq: I found the Spanish returned with immersion. I wasn't "back in the home country", but I was working two or three shifts a week with back-of-the-house bi- or tri-lingual Spanish-speakers who were using Spanish as a lingua franca, and I told them to treat me as an equal and include me in their non-anglosphere. I also befriended several Mexican families, was proposed a marriage of convenience, and lived with Mexicans for about 6 months which was when the dreaming in Spanish and hesitating in English began. If you want to recover the Chinese, get a basic primer and some roommates who speak your previous dialect, or at least socialize with them heavily, and exclude English entirely from dialog. Any using English will cripple your attempt. μηδείς (talk) 20:22, 12 August 2017 (UTC)[reply]

What do you mean by "crippling your attempt"? I learned Spanish in an Anglophone environment, and I could read, write, speak, and listen at the elementary level in Spanish. Also, it seems unrealistic that English would be forbidden. If Chinese is only used with the roommates, then the Chinese-speaking roommates may start feeling worried that their own English is not improving. I don't think living with roommates is a good option. Living in China may be better, but Dmcq may need a job to pay the bills and feed himself/herself. 50.4.236.254 (talk) 20:41, 12 August 2017 (UTC)[reply]

Non speako trollo. If you can bear to hear the truth you’ve spoken

Twisted by knaves to make a trap for fools....

--Rudyard Crippling

μηδείς (talk) 21:04, 12 August 2017 (UTC)[reply]

@ User talk:50.4.236.254) Think what μηδείς was alluding to, was that by not talking in one's mother language at all, it removes the temptation to translate what one has heard into ones mother's tongue of what has been said and then have to converts ones reply back into the language one is attempting to learn. Fluency is quicker to come, by the processes of total immersion. Aspro (talk) 21:36, 12 August 2017 (UTC)[reply]

I specifically addressed Dmcq's wondering whether he could "recall" the Chinese of his youth, not learn a new language de novo by taking classes. Fitty's response was simple contrarianism. I did not learn Spanish by taking classes, although I did buy the book on verbs (to better master the spoken preterite), did have an explicit knowledge of French, and did buy a dictionary. That lead to some laughs when I used highfalutin terms like vecindario for neighborhood when barrio was the informal standard. I asked the super of a building I wanted to move into in a Dominican area about the "vecindario", with the answer that "We cannot afford the luxury of vecindarios around here, we have only barrios. Perhaps your mercy should consider a skyscraper downtown?" (This was said jokingly, and I never used the term in speech again.) μηδείς (talk) 22:08, 12 August 2017 (UTC)[reply]

Yes, I know immersion helps with language fluency. Speaking like a native is a different matter. But Medeis also suggested that one could get roommates and only speak the roommates' language. I don't think this is a practical suggestion, because the roommates in an Anglophone environment may want to practice more English. One way is to tutor each other. The Chinese native speaker teaches conversational Chinese, and the English speaker teaches English. 50.4.236.254 (talk) 21:58, 12 August 2017 (UTC)[reply]

@Aspro: Yes, the OP's teacher's comment seems overblown, but I doubt I was actively using any Spanish at five after six months of pure English. Of course, my parents spoke English at home, not the language that was to be "lost". I know that I also lost my strong Southern accent very fast at that time, because I did not get picked on for it at school.

I wish I could remember some of the terms I hesitated with in English at this time. I 'remember' that they were nouns, but this was three decades ago, and it may very well have been idiomatic expressions. I also had more difficulty when the French and Spanish conflicted, such as the lack of a spoken preterite in French, while Spanish makes huge use of the preterite/imperfect contrast, such as the past forms supe/sabia que (preterite/imperfect) which mean "I knew", but specifically I discovered that vs. I was aware that. I also often "made up" pseudospanish, like asking Donde esta la fontana? (which was understood, but responded to with Hay una fuente aqui) by assuming that French fontaine had a direct cognate, but Spanish uses fuente from Latin fons with no additional suffix. μηδείς (talk) 20:22, 12 August 2017 (UTC)[reply]

Uhmm. Now having some hours to think about it, I did have problems with nouns when they applied to parts of the human body and bodily functions to a greater extent than with verbs and adjectives etc. which described those functions. Some words where OK in the school-yard but not OK at home.... and beyond. Which was a problem, since in one language some were OK yet, in other they where considered not OK which lead to adults to sometimes ask has the cat got your tongue? when I was not sure of the polite explanation in that language. But I can't remember any problems with very common nouns. You can bet though, I made up for that deficiency when I became a teenager and was never lost for something to say. Even, if I had to concatenate Latin, Greek and French into something that sounded impressive because I couldn’t think of anything better. Which might be the same reason μηδείς resorted to pseudospanish. The most important thing is to be able to communicate rather than be grammatically perfect – like wot I is now! Anyway the OP seems to have his question answered now. Aspro (talk) 00:16, 13 August 2017 (UTC)[reply]

@OP, while personal anecdotes may be interesting, they are no substitute for scientific study. This phenomenon has been studied and there are plenty of references available. The Psycholinguistics pioneer Wallace Lambert devoted his entire career to topics such as this. He called it "subtractive bilingualism" and if I recall correctly, "Bilingualism and language acquisition" is a good read. The book First Language Attrition (Seliger & Vago, editors) is also a good read and contains chapters that deal directly with your question. I can recommend others if you are interested in reading for yourself what the experts have to say.--William Thweatt ^Talk^Contribs 22:57, 12 August 2017 (UTC)[reply]

You're the only person who has answered the actual question instead of commenting on the personal anecdote in the OP with more personal anecdotes. This makes me happy.

50.4.236.254 (talk) 23:09, 12 August 2017 (UTC)[reply]

Welcome back, User:Russell.mo. Thanks for the smiley. I remembered the Dublin IP address, but the "makes me happy meme" is strong with you. Here's a discussion of your antics a while back. μηδείς (talk) 04:29, 13 August 2017 (UTC)[reply]

Sorry, but I don't know who in the world is User: Russell.mo. Next time, please ask for a CheckUser report. Also, I have read your discussions on the Reference Desk Talk Pages, and you repeatedly misidentify editors. 50.4.236.254 (talk) 04:37, 13 August 2017 (UTC)[reply]

Well since you now have had your question answered, perhaps you could tell us how fast one can lose a language? Dmcq (talk) 09:40, 13 August 2017 (UTC)[reply]

I was referring to the sources. William Thweatt provides me the sources, which seem interesting and may lead me to the answer, 50.4.236.254 (talk) 11:05, 13 August 2017 (UTC)[reply]

Well since you don't actually have an answer yet, how about expanding on the question. Why do you want to know this or what will it do for you? Dmcq (talk) 12:25, 13 August 2017 (UTC)[reply]

In Britain, amongst younger speakers, there is frequently rising intonation at the end of a sentence even when a question is not being asked. I believe this spread from the United States. 82.14.24.95 (talk) 14:53, 13 August 2017 (UTC)[reply]

Mottaphobia

(Inspired by the arachnophobia question above) A few questions about mottaphobia, to help me shed some light on this condition: (1) Does it tend to run in families? (2) Does it usually occur as a generalized phobia (fear of all butterflies and moths), or as a fear of 1 or more particular species thereof -- and if the latter, which species are the most likely to trigger this response? (Speaking for me personally, I'm perfectly OK with most butterfly species, but swallowtail butterflies totally creep me out!) And (3): How much comorbidity is there with other anxiety disorders (particularly with other animal phobias)? 2601:646:8E01:7E0B:21B1:8CA4:6F9F:6132 (talk) 08:41, 12 August 2017 (UTC)[reply]

I wonder of the trailing wing parts of a swallowtail butterfly such as a Protographium marcellus remind you of the trailing legs of a wasp in flight: [37]. That might cause the reaction, especially if you've been stung. StuRat (talk) 13:03, 12 August 2017 (UTC)[reply]

I think it has to do with their large size (up to 8 inches or more!) more than anything else (although their shape and coloration does play a reinforcing role) -- their juveniles don't scare me as long as they're less than 4 inches or so in size. So, should I take this as evidence that swallowtails are more likely to cause this reaction than most other species? 2601:646:8E01:7E0B:21B1:8CA4:6F9F:6132 (talk) 05:05, 13 August 2017 (UTC)[reply]

You do realize that a juvenile butterfly is a caterpillar? The butterfly is the last instar of the organism, it does not molt or grow after appearing from the chrysalis: there are no little butterflies growing into bigger butterflies; it is an impossibility. μηδείς (talk) 15:32, 13 August 2017 (UTC)[reply]

Eye color and light absorption

Eye_color#Brown says that due to high melanin concentration in the iris this color absorbs both shorter and longer wavelengths. Does it mean that brown and dark brown eyes are less protected against direct sunlight, compared to other eye colors, similar to sun glasses and UV filter? I read that in case of hair color the black ~~absorps~~ absorbs more heat than blonde so that the former becomes warmer after 5 minutes of direct sunlight. Brandmeister^talk 21:43, 12 August 2017 (UTC)[reply]

No, not if you mean light hitting the retina, because the eye color is not in the path of light that hits the cornea. That's a bit like saying the paint color on your car affects how much light makes it through the windshield (although in that case at least some light is reflected off the paint into the windows, unlike with eyes).

Now, if you are asking if the pigment itself is more likely to be damaged by UV light, that's possible. I don't know the answer to that. StuRat (talk) 21:45, 12 August 2017 (UTC)[reply]

You have the reasoning backwards. Like pale skin, blue eyes are more sensitive to sunlight. The dark iris protects the sensitive retina by keeping out more light. μηδείς (talk) 02:29, 13 August 2017 (UTC)[reply]
- Yep, that makes sense. But I also wonder whether due to absorption of both shorter and longer wavelengths dark eyes have somewhat better vision than other colors? Brandmeister^talk 07:39, 13 August 2017 (UTC)[reply]
Does a significant amount of light reach the retina after passing through the iris? It's the light passing through the pupil that focuses on the retina. Dbfirs 06:14, 13 August 2017 (UTC)[reply]

That's the whole reason the iris is pigmented; to allow a variable aperture, the closure of which blocks more light. The pigment does the blocking. If brown irises were to let only 1% of light to pass, while blue irises allowed 2% (I'm making those numbers up) then people with blue irises would still be getting twice the amount of extra light. Studies vary in their conclusions, but the overall picture is that blue-eyed people get much more UV damage overall. Unexpectedly, one year-2000 study did show brown-eyed people got more cataracts, but the reasons for this are speculative. μηδείς (talk) 15:55, 13 August 2017 (UTC)[reply]

August 13

Nicotine addiction

request for medical advice, user wishes to take a drug and wants to know how it will affect him

The following discussion has been closed. Please do not modify it.

I'm curious what nicotine addiction feels like so I plan on doing e-cigarette's. I'm fine with the crash I'll experience for a few weeks after quitting but I'm wondering if it'll be like low-level craving it for years/rest of my life? I don't want to wake up everyday forever thinking damn I wish I had some nicotine. 2.102.184.47 (talk) 03:44, 13 August 2017 (UTC)[reply]

Please read the instructions at the top of the page, we cannot make medical predictions or speculate on the future. μηδείς (talk) 04:05, 13 August 2017 (UTC)[reply]

I think dismissing this is an unjustifiable cop-out. Nicotine is not a prescribed medication, and sources on the rapid onset of addiction are available: [38] [39] [40] Note these sources all agree that one can become addicted within two days, though it may not happen that fast. As in Charlottesville, there is more harm to be done by suppressing discussion than by permitting it. Wnt (talk) 12:05, 13 August 2017 (UTC)[reply]

The FDA has regulated all nicotine products since August 2016 https://www.fda.gov/tobaccoproducts/labeling/rulesregulationsguidance/ucm394909.htm. This is a request for personal advice on how the use of a drug will affect the individual, a classic no-no. μηδείς (talk) 15:24, 13 August 2017 (UTC)[reply]

identify an insect

Triangular shaped bug about 5-7 millimetres long. I think it is initially translucent, then green and finally brown (not sure though). Dozens of this insect are present on the stalks of a bean plant. It is not feeding on the leaves, but probably on the stalk. Not found on nearby plants until the bean stack was cut down / pruned. Ants seem to interacting with it a lot (I think). Google reverse image search wasn't helpful.

— Preceding unsigned comment added by Cplusplusboy (talk • contribs) 07:04, 13 August 2017 (UTC)[reply]

These look like larvae of some species of Cicadellidae or leafhoppers, sap sucking insects that probably produce honeydew which accounts for the opportunistic (or farming) ants. There are very many species and some specialist sources will probably be required to establish the exact indentification. Compare with this image http://www.ozanimals.com/Insect/Leafhopper-larvae/Cicadllidae%20family/spp2.html. Richard Avery (talk) 10:18, 13 August 2017 (UTC)[reply]

The thorn shape reminds me of a treehopper - for example, [41] reviews that this shape is pretty representative, and involves a much modified pronotum... the setae do make it seem more like a nymph, though early treehopper stages apparently don't have the thorn shape. this photo of Acanthuchus trispinifer looks similar but not identical to me. Our resources, including Wikispecies, seem almost entirely deficient on any kind of Terentiini other than this species. Wnt (talk) 11:56, 13 August 2017 (UTC)[reply]

The pictures in the landcareresearch.co.nz link are the ones (unless this shape and colour are commonly found in other species). The green photos with the pyramid shaped head and curved tail I posted are nymphs and the brown ones not posted here is the adult tri-horned treehopper as per the website. Thanks Cplusplusboy (talk) 16:37, 13 August 2017 (UTC)[reply]

Pressure during gravitational collapse

How much pressure approximately (say, in GPa) is generated by gravitational compression during gravitational collapse of a star (also in cases of black holes)? Thanks.--212.180.235.46 (talk) 14:46, 13 August 2017 (UTC)[reply]