Wikipedia:Reference desk/Archives/Science/2013 January 22

= January 22 =

In time of need, can the Male body metabolize Gynecomastia's Connective tissue?
I'm totally serious with this question. could it be that the body will use it's relevant contents to make needed substances? thanks ! — Preceding unsigned comment added by 79.176.113.107 (talk) 04:03, 22 January 2013 (UTC)


 * Your question is not clear. But the body will certainly use the fat reserve in case it need to do so. It does not matter where the fat is accumulated. --PlanetEditor (talk) 04:32, 22 January 2013 (UTC)


 * But comrade, i don't talk about Fat tissue, but of Connective tissue. — Preceding unsigned comment added by 79.176.113.107 (talk) 04:48, 22 January 2013 (UTC)


 * Fat tissue is a connective tissue. --PlanetEditor (talk) 05:12, 22 January 2013 (UTC)


 * oh yes?, because in any occasion, even when i heard physicians (plastic surgeons) speak about this, they always impressed me that the Gynecomastia tissue is of some "special" kind of "Connective" tissue, that cannot be "burn" (Beta-oxidize) like regular fat. (but i ask of metabolism in general).


 * Connective tissue. μηδείς (talk) 04:40, 22 January 2013 (UTC)


 * Breasts are composed of a combo of tissues, but a fair amount of it is fat (in adipose tissue). As such, breast size is substantially reduced when either women or men lose weight.  However, too rapid of weight loss could result in sagging skin, particularly in older individuals. StuRat (talk) 14:06, 22 January 2013 (UTC)
 * okey, but we know that except fat, also muscle could metabolize by the body. so what about the other lean "Breastish" tissues - can they be metabolize too? — Preceding unsigned comment added by 79.176.113.107 (talk) 01:31, 23 January 2013 (UTC)
 * So far as I know, the other tissue is mammary gland tissue, which is indeed not a connective tissue at all but an epithelium. The effect of starvation on them must not be too great, because once food is administered, gynecomastia can then result even in previously unaffected men.  I suppose this tracks back to the "apparent purpose" of mammary tissue, for feeding, which should go on regardless of food supply.  Wnt (talk) 19:27, 23 January 2013 (UTC)

RNA primer instead of DNA prime
Why RNA primers instead of DNA primes, are used in the replication of the lagging strand? What could the evolutionary advantage of this? Dnakid (talk) 06:31, 22 January 2013 (UTC)
 * Maybe because they can be more easily removed when no longer needed? Or perhaps their synthesis requires less energy than for DNA? 24.23.196.85 (talk) 09:00, 22 January 2013 (UTC)
 * DNA polymerase 3 only adds 3->5, but RNA polymerase can add where its complement is on the ssDNA. The RNA goes first and it provides that 5 and 3 end. The 3 end for the DNA polymerase to add DNA. It's more complicated than this, but this is the general answer. Smallman12q (talk) 04:15, 23 January 2013 (UTC)
 * In a sense the question isn't philosophically valid - evolution doesn't actually need a reason for doing something. Nonetheless, the "design" is often plainly visible - leading to the conundrum that it is very difficult to prove what seems obvious, and we end up with Just-so stories.  But - without claiming that this is "the" reason - I will point out that when an enzyme attempts to prime DNA synthesis, every now and then something will go wrong and the primer won't get a chance to extend before it flies off into solution never to be recovered.  In that instance it is far more predictable what will happen if it is RNA, which is subject to the continual attacks of RNAse, than if it is a piece of DNA that, in theory, could end up being stuffed into the genome somewhere it doesn't belong. Wnt (talk) 19:27, 23 January 2013 (UTC)

Why were my questions removed?!
I've asked two questions about biochemistry (one about chloral hydrate, and one about drug-induced amnesia), and both were removed with NO explanation given! Why is this?! 24.23.196.85 (talk) 06:51, 22 January 2013 (UTC)


 * They were removed (not by me, but by someone else) as a violation of Medical disclaimer. -- Jayron  32  06:56, 22 January 2013 (UTC)


 * All right, then let me explain why I asked them: I was NOT asking for medical advice, but researching for a detective novel. 24.23.196.85 (talk) 07:00, 22 January 2013 (UTC)


 * I suggest you restore them, and add that bit of info. StuRat (talk) 07:05, 22 January 2013 (UTC)


 * I suggest that you don't, as medical advice requests aren't changed by adding sentences which claim that what they are asking for isn't medical advice. -- Jayron  32  07:06, 22 January 2013 (UTC)


 * I had actually typed up a response to the first question, but was hit with an edit conflict when I tried to save the page. I understand why they were removed, but I tend to think that the IP is telling the truth when he says it's for research; I am a writer and my Google search history can be a tad unsettling from time to time. I see nothing in the reference desk guidelines that prevents asking questions related to the biological effects of certain chemicals, but we will stop short of actually advising someone to do (or not do) something hazardous. Evanh2008 (talk&#124;contribs) 07:12, 22 January 2013 (UTC)


 * If this is the same I/P who has asked many Q's for stories before, it should be reasonable to Assume Good Faith that they are, indeed, asking for that reason now. It's only medical advice if they actually intend to do it. StuRat (talk) 07:13, 22 January 2013 (UTC)


 * Go ahead, be my guest. Have fun.  -- Jayron  32  07:15, 22 January 2013 (UTC)


 * Just like to note that the editor who removed the questions did provide an explanation in their edit summary: Wikipedia does not give advice on how to administer toxins etc. I suggest any further discussion of this belongs either at their talk page or at the Ref Desk talk page. Gandalf61 (talk) 07:21, 22 January 2013 (UTC)

Bad guys drugging good guys
Two questions that were mistakenly removed as medical advice:

(1) If chloral hydrate is added to spring water (as opposed to a flavored beverage like wine, apple juice, etc.), would the intended victim be able to detect it by taste alone?

(2) What drug(s) can induce temporary amnesia?

NOTE: This is NOT for medical advice -- it's for a modern-day detective novel that incorporates plot elements from Norse mythology, which I've outlined a few years ago but never got around to writing because I realized the project was too much over my head. I intend to come back to it soon, though, when I'm done with the four titles I'm working on simultaneously right now. 24.23.196.85 (talk) 08:49, 22 January 2013 (UTC)


 * For (2), see Drug-induced amnesia. — Quondum 09:41, 22 January 2013 (UTC)
 * For (1), I tasted chloral hydrate many years ago (I was prescribed it; long story), and I'm pretty sure I'd be able to detect it in just about anything. Imagine something somewhere on the continuum between over-chlorinated tap water and chimney ash. The book sounds interesting, by the way. If you need a beta/proofreader I'd be glad to give it a look. Evanh2008 (talk&#124;contribs) 09:47, 22 January 2013 (UTC)


 * here is a description of the taste. As with anything on the Internet, it may be completely made up. --Guy Macon (talk) 10:58, 22 January 2013 (UTC)
 * (2) See retrograde amnesia, date rape drug e.g. roofie. Wnt (talk) 16:43, 22 January 2013 (UTC)


 * Thanks, everyone! I don't want to give too much away, but my first question is for a scene near the end, right after an intense firefight where one of the good guys knocks out a main battle tank, when one of the bad guys tries to give him (and the rest of the squad) water with chloral hydrate, in order to put them all to sleep -- but the good guy becomes suspicious and thwarts this.  And my second question is for another scene, where another villain (a woman this time) gives the above-mentioned commando a two-component "love potion" (she slips it into his beer while her accomplices distract him) and tries to seduce him -- she almost succeeds, but just as he's about to come to her bed, his memory starts to come back and he runs from her place in just his underwear (but unfortunately for him, not before she takes several compromising photos of him with her and uses them to turn his own girlfriend, a field agent in her own right, against him).  For the second question, in particular, I need to know the composition of the "love potion" so that my characters could figure it out.  I've decided to make it a two-component drug: one component would be a straight aphrodisiac, to increase the victim's sexual desire (probably some kind of zinc-testosterone complex), and the second component would cause temporary amnesia, to make him forget about his current relationship.  So in effect, the potion will make him horny for whichever woman he happens to be looking at/talking to (as long as she's not ugly), regardless of him being in love with someone else -- but she'll still have to do the work as well.  :-) 24.23.196.85 (talk) 02:22, 23 January 2013 (UTC)
 * Testosterone for an aphrodisiac abuses my credulity - there are lots of men who take testosterone supplements, but while they are said to restore lost libido for some I don't think they are particularly effective in making a man fall for someone on the spot, and also many who take anabolic steroids, with rather less than indifferent results. I tend to give more credit to pheromones, which seem to have potent effects, but an effective aphrodisiac is definitely one of those things the audience will find hard to be persuaded by.  Might be tempting to mix up some ideas and add some blur.  For example, for the pheromones I recall reading a Santeria formulation in David St. Clair's book "Drum and Candle", in which AFAIR scrambled eggs are poured between the woman's thighs and served to the man in an omelet.  To this you could plausibly add some named herbs like Yohimbe, and then hint at more "rare herbs and spices" known only to great obeahs, etc.  We might not believe it but we can't be sure it won't work, because the ancients were much better at medicine than people give them credit for, and some of the old herbal preparations yield up new secrets to science every year. Wnt (talk) 03:43, 23 January 2013 (UTC)


 * Testosterone injections are known to cause priapism. Perhaps that does or doesn't count as an aphrodisiac. μηδείς (talk) 03:52, 23 January 2013 (UTC)


 * Technically it doesn't -- the point is to increase desire (which is not just physical but psychological as well). How about bremelanotide? 24.23.196.85 (talk) 04:59, 23 January 2013 (UTC)
 * Thanks for pointing to me to that interesting story. The more memorable keyword is Melanotan.  Fun in the sun, bottled, and (terribly wicked) sometimes even sold without dutiful submission to the cartel. Wnt (talk) 17:08, 23 January 2013 (UTC)
 * That seems like a good idea too. Also, if it results in noticeable skin darkening (the guy is a typical pure-blood Teuton from Bavaria and has a pretty light complexion), that could also be a clue for the detectives that something is amiss.  :-) 24.23.196.85 (talk) 05:08, 24 January 2013 (UTC)

Experimental Medicine
I remember once reading a story in reader's digest about an experimental medicine that would significantly reduce the need for sleep a person would need, but I threw away the copy of the magazine. Any ideas on what chemical it was? Rabuve (talk) 09:04, 22 January 2013 (UTC)


 * Modafinil is a possibility depending on when the article was published.Phoenixia1177 (talk) 09:16, 22 January 2013 (UTC)

Trip hammer mechanics
How does a trip hammer work? The article has no good picture and I can not figure out myself how it works. Especially the mechanism by which the hammer is released gives me a headache. There must be really big stress and wear on the material. How was this done in historical times, with wood and little to none metal? 93.132.137.91 (talk) 13:30, 22 January 2013 (UTC)


 * Have you watched the video in the article? It's fairly clear that there is no mechanism specifically to release the hammer; it just falls off the protruding part of the cam as the cam rises and rotates out from under it. And the article reveals that the earliest trip hammers were around 2,200 years ago, which is well after the iron age. China and Rome (where these hammers originate) both fielded large armies in those days armed and armoured with metal. There wasn't 'little to no metal' at all. AlexTiefling (talk) 13:34, 22 January 2013 (UTC)


 * No. My computer can't play videos. That there was iron does not imply that it was cheaply available. My problem with understanding is exactly the moment when the hammer "falls off". Tere must be friction and high forces. 93.132.137.91 (talk) 13:41, 22 January 2013 (UTC)


 * As far as I can tell, the iron casing of the cam is sufficiently polished that the friction isn't a big deal. The cam is sufficiently cleverly shaped that it lifts the hammer and then drops it fairly cleanly; it's all in the profile of the cam. And I used the existence of huge standing armies with metal weapons as evidence that metal was plentiful. Whether it was cheap doesn't necessarily matter, but in practice I believe that iron was pretty cheap in both late Republican Rome and early Imperial China. Why would you think otherwise? We have literally tons of iron artefacts from this era, as well as extensive written sources about the relatively casual use of iron. AlexTiefling (talk) 13:54, 22 January 2013 (UTC)


 * Accidentally I came across the trip hammer question when thinking about early iron making. The process must have been very labor intensive, first making charcoal, mining and grinding the ore, smelting in a bloomery and then hammering the slag out. The article Obolus mentions the Spartans had rod shaped iron as a currency, so it could not have been all too plentiful.


 * Back to the mechanical problem. The hammer must be lifted by "some peace of material", and the contact area gets smaller and smaller, until the hammer drops off. So just before that, the area on which the hammer rests must be extremely small, putting large stress on the material. I do believe you that it works, but I don't understand why. 93.132.137.91 (talk) 14:41, 22 January 2013 (UTC)


 * (outdent) Because the cam is curved rather than pointed, I think the area under pressure remains quite high until almost the last moment, and then reduces rapidly. So there isn't any part to break off, or anything. Moreover, the cam itself is made of iron, or of wood heavily shod with iron. So even a relatively small part of the whole is still an immense object, not prone to snapping under pressure.
 * (The Spartan obol appears to have been an anachronism even 2-4 centuries before the first tilt hammers became widespread. It's notable that the Romans were famed for their engineering acumen, constructing the first trans-continental highways, minutely engineered aqueducts, and pontoon bridges that spanned Europe's widest rivers and most notorious maritime straits. Smelting iron on a larger and more efficient scale than individual Greek city states was not a problem for them.) AlexTiefling (talk) 14:53, 22 January 2013 (UTC)


 * Thanks, I think the rounded part is what circumvents my understanding problem. And for the iron, I think it simply accumulates over time, as it is not consumed. 93.132.137.91 (talk) 15:27, 22 January 2013 (UTC)


 * Definitely try to watch the video on another computer. It certainly helped me understand. And the iron thing is complex: it can be recycled, so the amount of iron in circulation will increase over time. But it it isn't always; the sheer mass of iron artefacts from ancient Roman sites shows that a lot of it ended up in latrines, rubbish pits, ditches, etc. And it also rusts - stainless steel being a much more modern invention - so the iron artefacts we've got are often badly corroded. Even if you retrieved a rusty infantry sword and melted it down to make a hammer-head or something, you'd end up with a lot less iron than had been in the sword when it was new. So the efficiency and breadth of the Roman (or Chinese) industrial economy was still probably a major factor. (I've been down a Roman gold mine, years ago. Those guys were seriously accomplished engineers.) AlexTiefling (talk) 15:31, 22 January 2013 (UTC)
 * Related, but somewhat off-topic: does a user without video access see the still image?  If so, can that image frame be specified?  The current image is not particularly useful (the outside of the building) - a video frame from the operating mechanism could explain a lot: "a picture is worth [many] words".  A trip hammer is a remarkably simple mechanism; the article should include a diagram or something. ~Just my 2¢, ~:(talk) 20:02, 22 January 2013 (UTC): modified:74.60.29.141 (talk) 20:21, 22 January 2013 (UTC) 
 * E.g.:


 * File:Frohnauer Hammer Innenraum.jpg is a low-tech (simple spokes rather than smooth cam to lift). DMacks (talk) 20:16, 22 January 2013 (UTC)

Requirements of control panel for seismic relay.
Kindly let me know whether an electrical/control panel conforming to Seismic catagory/class III can be used for mounting/installing the triaxial(seismic) relay installed at suitable location for the power supply to plant.

I know that an electrical/control panel conforming to Seismic catagory/class I or II can be used for mounting/installing the above said tripping relay. — Preceding unsigned comment added by Ashutoshsds (talk • contribs) 14:07, 22 January 2013 (UTC)


 * You are going to have to be more specific. In particular, you have to specify what standards you are trying to meet. I am pretty sure it isn't UFGS (Unified Facilities Guide Specifications) because UFGS Seismic Design Categories are specified with letters such as A or B, whereas you mention "class III". Are you trying to meet EN (European Norm) standards? IBC (International Building Code)? Something related to the NRC (Nuclear Regulatory Commission)?


 * Furthermore, the basic earthquake safety standards for electrical control panels have different goals than the standards for seismic trip relays. An electrical control panel that is completely isolated from any possible ground movement would pass with flying colors, but a seismic detector wouldn't work at all under those conditions. Likewise, being solidly mounted to the foundation of a building and thus able to experience full earthquake shaking works fine for a seismic sensor but not for electrical equipment such as circuit breakers that may chatter if shaken hard enough.


 * In order to get any sort of sensible answer, you are going to have to describe what you are trying to do and exactly which standards you are trying to meet. --Guy Macon (talk) 18:15, 22 January 2013 (UTC)

Fire Drills
I'm having trouble finding any information on how effective fire drills are at preventing death and injury based on the frequency of the drills. I'm especially interested in whether areas/facilities where extremely frequent fire drills, in addition to false alarms of any type, happen have an increased likelihood of death or injury during actual emergency situations. (The reason being that people might begin to ignore the alarm in certain facilities like a dormitory or office.) Lord Arador (talk) 14:29, 22 January 2013 (UTC)


 * Well a quick back of envelope calculation by me indicates it is senseless to have fire drills more than once a year in any place except dwellings where people cook and sleep. The basics are that you have something like a 1 in 2000 chance of dying in a fire over your entire life in Britain for instance, but about 75% of that is at home and half of the lot is because people were too drunk. The rest are split evenly between other buildings, vehicles, and outside. That means you have something like most places doing fire drills the chance of the people dying of a fire per year is something like 1 in 30000, i.e. they lose on average 1/30000 of a year per year due to the risk = about 18 minutes. You should only waste of that order of magnitude or less of their time per year, i.e. have one fire drill a year. Just my thoughts - I'm sure the fire department will say otherwise! Your best bet is have good obvious exit direction notices they'll follow with an alternative depending on where the fire is. Dmcq (talk) 16:27, 22 January 2013 (UTC)


 * You're missing the possibility that the reason why deaths are so low in these kinds of buildings is because of fire drills. Stop the fire drills and maybe those deaths would go through the roof.  It's like saying "Hardly any drivers die in low speed car accidents - so why should we bother with seatbelts?!".  To do a proper study, you'd have to look back to a time before fire drills. SteveBaker (talk) 20:49, 22 January 2013 (UTC)


 * The risks would have to go up very fast indeed for that sort of thing to make an appreciable difference and your comparison to driving is totally wrong - if people could keep their speed down then there wouldn't be much point in seat belts. It is up to people who deprive us of a portion of our lives to show that what they have substituted is worth it rather than up to the people who have shown that it probably isn't worth while. And by the way a pet peeve of mine is fire doors on halls - these as far as I can see cause more deaths than they save because people lock them and they are too strong to break through. Saying they should not be locked during a concert is just missing the point of what reality is. Dmcq (talk) 22:31, 22 January 2013 (UTC)


 * It also depends on the structure. Pretty much anyone can figure out which way the exit is in a single-story detached house, but some offices and factories are like mazes. It sounds like Lord Arador might be in an environment where they do an excessive amount of fire drills. In such a case it is worth asking whether any time has been spent on fire education. Knowing where the exits are is a Good Thing, but have they been taught about crawling vs. walking in a smoke-filled hallway? About feeling a door to see if it is hot before opening it? How to effectively use a fire extinguisher or fire hose? Have they been told about propping open fire doors? When somebody does prop open a fire door, is there someone who confronts them for endangering everyone? Our article on Fire safety is a good place to start. --Guy Macon (talk) 18:29, 22 January 2013 (UTC)


 * In my way of looking at it if you have some people per floor with health and safety responsibilities as part of their job then you can move some of the life costs over to them so it becomes worthwhile spending the time giving them proper training. Dmcq (talk) 22:55, 22 January 2013 (UTC)


 * The question I always had, when in school, was whether fire drills mid-winter were likely to kill more children than they saved, since it meant going outside in extreme cold, without a coat. The problem is, kids who got sick and subsequently died weren't likely to have the cause of death listed as "fire drill", so stats would be unreliable. StuRat (talk) 19:58, 22 January 2013 (UTC)


 * Having experince as a fire warden in an 18 storey office building, I offer the following OR from my experience:-
 * When we moved into the building, after a few weeks we had a full evacuation fire drill, with fire brigade signalling turned off. We warned all tenants a few days in advance.  It took about 30 minutes to get everyone out and caused significant disruption to city traffic, as the only usuable assembly area was 2 block away requiring a road crossing.  About 5% of staff dissappeared.  If there had been a fire, 20 minutes evac time would have resulted in quite a few deaths.  All fire wardens met later and discused what went wrong, then we held talks on all floors.  We did it all again 3 months later, and achieved a full evac in 14 minutes, which is quite good, and we didn't cause traffic disruption.  Another 3 months, we did it again, again a good fast orderly evac, 14 minutes.  Everybody able bodied went down the stairs on the inside, as they were taught to do (firemen are taught to ascend on the outside).  Minders looked after the few folk who were in wheelchairs (Australian practice is to leave folk who cannot walk in designated areas with a minder for communication. The fire brigade is responsible for transporting them out) About 6 months later, we decided to do another drill - this time without warning the tenants, and we included the fire brigade in the drill.  Result:  A terrible mess.  Some people assumed it was another drill and decided to continue their phone calls etc.  Others, perhaps triggered by the sight and sound of fire engines, panicked.  It took us 35 minutes to get every able bodied person out. A guy in a wheelchair was abandoned.  So, what do I think?  Ordinary drills with everyone knowing its a drill help the wardens learn what to do, but don't do too many of them.  Every firewarden in a multistorey building should experience a full without warning drill - without it they will be overconfident.
 * It is worthwhile getting external audit people to assist with drills. Fire brigades love doing it.  In another office tower I worked in, the auditors used smoke bombs, and they dissabled the public address system, simulating a PA system fault.  The result was a complete shambles, because the stupid wardens had not maintained the batteries in their loudhailers and 2-way radios.  Wardens learnt a lot that day - not the least because 3 hours of work for 1500 people were lost - company top managers were not amused. Another time the building was left unsecured, so folk off the street could go where they liked.  That's bad - very bad.
 * Floda 120.145.134.18 (talk) 00:23, 23 January 2013 (UTC)


 * Very interesting. What do you mean by going down on the inside?  Hugging the axis of the stairwell? μηδείς (talk) 02:51, 23 January 2013 (UTC)


 * While American buildings tend to only have stairs in the center utility corridor, to avoid taking up valuable window space, in other nations they frequently have one set in the center and more stairs on the outside wall. This has the added advantage, that, during the day, they can be lit with natural light from the windows, if the stairway lighting fails.  This approach also increases capacity and thus decreases evacuation time. StuRat (talk) 07:26, 23 January 2013 (UTC)


 * StuRat has jumped in without thinking on things he knows nothing about, as he often does. You get buildings with stairs and lifts in a more or less central core, and you get buildings with stairs at the ends.  Neither is peculiar to the USA or anywhere else.  "Going down on the inside" has nothing to do with that.  One evacuates on ALL available stairs of course.  And all stairs must, by building code, have battery backed emergency lighting.  Any one stair well, per building code, is wide enough so that standard ambulance stretchers can be carried up and down - this makes them wide enough so that 3 or 4 largish people can go down or up side by side together, though that is not the intention.  There is a grab rail on the walls (the "outside grab rail") and a banister/grab rail in the centre (the stairwell "axis" if you will -viualise the stairs turning 180 degrees on each floor landing).  In Australia, people are supposed to evacuate with their hands on the inside/centre grab rail.  This has four advantages:  1) it is a lot safer - people are less likely to trip or fall with their hand continuously on the centre grab rail;  2) it makes for a single-file proceding down the stairs, without fitter (or more panicky) people trying to overtake the slower ones. This actually helps achieve a minimum time evacuation. 3) it keeps the landing doors clear so fire wardens can use them. 4) fire brigade officers are trained to go up the stairs on the "outside" that is against the wall side or "outside" grab rail.  In other words, the fire fighters can charge up tye stairs simultaneously with the people leaving, without anybody getting in the way.  The building designated fire wardens can also use this clear path.  Floda 60.231.240.175 (talk) 10:36, 23 January 2013 (UTC)


 * I take it this is Wickwack hiding under a new name ? Either that or personal attacks in place of references have become the norm for Aussies.  Now to take on your usual unreferenced opinions, with references:  First, you said "One evacuates on ALL available stairs of course.".  No, it's much better if one stairway is used for access by emergency personnel, and the rest for evacuation.  See here: : "This left only stair A for both occupant egress and fire attack.  The fire department could not begin to attack the fire until evacuation was complete – about one hour".  As for emergency lighting, that's not much, especially if some smoke has found it's way into the stairwell.  Large windows provide far more light.  Windows in the doors are also helpful, both for light and so you can check for flaming debris before opening the door: .  And, when fumbling around blind, having people going in two directions is likely to cause collisions. StuRat (talk) 04:34, 25 January 2013 (UTC)
 * I agree with Floda. A careful read of all this shows that Flda was talking specifically about how evacuation training is done in Australia, and I can confirm that her(?) description is accurate.  StuRat first offered a comment about USA buildings vs buildings in other countries which is obviously something he made up.  In StuRat's last post above, his link [4] goes to a site that is off-topic.  His link [3] supports his view on the use of stairwells, but is an USA document and has no bearing on Australian practice.  It is well known outside the USA that the USA often does things different to international standards.  Having said that, StuRat's link [3], while having credibility as some sort of official report, and StuRat's opinions, do not make much sense to me.  They talk about evacuating times in terms of an hour.  That might have been the best that could be done in the World Trade Centre on 9/11, but if an Australian fire brigade or auditor witnessed a city office tower taking 1 hour to evacuate, they would sure have plenty to say about it.  If it wasn't fixed promptly, ther would be work orders at the very least.  Floda's 14 minutes is about right.  Evacs should certainly take under 20 minutes regardless of building size.  Not using all available routes of egress is stupid, as the more you use, the faster the evac will be - and the fire brigade, due to city traffic, won't even arive for at least 15 minutes, even though their comms centres have control over traffic lights.  It should be the case that by the time the fire brigade arrives, all able bodied people should have left the building.  Yes, folk fumbling/milling about will cause delays (and accidents durinmg drills) - that why Australian practice is to teach folk to go single file continuously touching the inner bannister rail, as Floda said.  Sunlight doesn't work at night - when many fires occur.  In any case, it was learnt a long time ago that fires spread from floor to floor via lift shafts, stairwells, and aircon ducts.  That's why building codes require that such things must be constructed to prevents such things.  When buildings go into fire mode, louvres automatically close off aircon, and lifts are shut down.  Stairwell doors must be fire rated, Stairwells are designed to make smoke in them unlikely - pressurisation from above is a typical, but not the only, method. I'm not going to say that stairwell doors cannot have windows, though I haven't seen windows in stairwell doors.  If windows are fitted, they will have to be fire rated, so they cannot use window glass. There are two, and only two, reasons why persons other than fire brigade officers and fire wardens should re-enter a floor from as stairwell: 1) they are directed to do so by a fire warden, 2) There is clearly a fire lower down within the stairwell (which would be an extremely rare event). Once you enter the stairwell, you prcoeed until you reach the ground floor building exit.  Ratbone 124.182.17.177 (talk) 12:31, 26 January 2013 (UTC)


 * Indeed very interesting. That reminds me of a strange inconsistency with drills: with movies about the military (which is all I know about them) they are always saying "this is not a drill!" in emergency situations.  And indeed in recent movies they even indicate when something is a drill.  But there isn't an immediate indication with fire drills when it is fake and when it is real.  My thought is that the military must know more about drilling than anybody, so if they really do tell people, that would be a good idea for fire drills...  (On the other hand there's Sean Baker, though that sounds like the exception that proves the rule) Wnt (talk) 03:25, 23 January 2013 (UTC)


 * Anything the military do or don't do has no bearing on civilian practice. Military personell are trained to absolutely obey any order without hesitation and without question.  When a platoon member calls "DOWN!", you don't think "Oh! 'down' - I remember doing that in boot camp."  You instantly on reflex go flat on your stomach on the ground - or you die from enemy bullets.  Civilians don't have that training.  If you tell military guys 'Wait in the floor assembly area till I call Go!" - they'll do just that.  If you tell civilians to do that, which as a fire warden you will if you know the stairwell is already clogged but will clear in 2 minutes, you'll get most doing what you want, some idiots returning to their desks, and some idiots will think "Stuff you - I'm leaving", and enter the stairwell anyway.  And some idiots will want to ask questions or debate the point with you.  You need to think on your feet as a fire warden in an office tower.  And get folk you can trust guarding the doors if necessary. There's enough people on each floor in large office towers to completely fill 4 or 5 flights of stairs, so wardens need to coordinate and stagger each floor's evacuation, so that each stair well is fully occupied but only just fully occupied, for as much of the evac time as possible. Floda 120.145.189.213 (talk) 11:44, 23 January 2013 (UTC)


 * In my school days we could see if it was a drill based on whether the office secretaries were still at their desks, ignoring the alarms. Someguy1221 (talk) 10:50, 23 January 2013 (UTC)


 * Another reason, from experience, for doing drills. One time I was working in a customer building, a largish office tower.  It was after business hours, and all fire wardens had left for the day, but there were still quite a few women working.  Something tripped the fire alarm - fortunately a false alarm.  The building went automatically into fire mode:  First, the Alarm tone sounded on all floors - and kept on sounding.  The airconditioning shut down.  A moderately loud humming noise started.  Then, we could hear the Evacuate tone sounding sequentially floor by floor.  Then Evac tone sounded on my floor.  By this time the girls were loking pretty worried, and they were saying to each other, "What should we do."  I called out "evacuate immediately of course - via the nearest stairs".  Some girls went to the lifts, which of course had automatically shut down.  Some girls came with me to a stairwell.  A girl got there first, and said to me, with much alarm in her voice, "This door is locked!".  At that point I realised what the humming was - this was a building that, when in fire mode, pressurises the stairwells with a huge fan at the top, in order to prevent fire travelling up the stairwells.  I tried the door - sure enough it would not open with normal force.  So I pushed hard and it opened.  I and the girls then proceeded down the stairs.  As I got near the door to the next floor down, above the noise of the fan, I could hear a lot of screaming and yelling - staff on that floor obviously thought they were locked inside a burning building.  I had some pointed words, about conducting proper drills, to say to the building Management next morning.  Ratbone 120.145.189.213 (talk) 12:54, 23 January 2013 (UTC)


 * It was daft not having a notice beside the doors warning about that along with any other vital information. Enough people working in buildings do read the notices eventually so most groups would be okay. Dmcq (talk) 17:16, 23 January 2013 (UTC)


 * Quite right, though it may be that the pressurisation was excessive. However, if they had held a fire drill, not only would sufficient staff be aware of it anyway, someone would have pointed out the need for signage.  It illustrates the two main reasons for holding drills:  1) Teaching people what to do and not do, and 2) discovering what's not right.  Ratbone 120.145.160.76 (talk) 01:56, 24 January 2013 (UTC)


 * The pressurization in that case was excessive: it's not supposed to lead to excessive door opening force. In response to the stair arrangement tangent a couple of paragraphs up the page, codes are generally written to establish a minimum standard for "remoteness" of exits on each floor, usually half the longest diagonal distance between corners, which can be reduced if sprinklers are provided. Stair locations are also dictated by maximum dead end distance and common path of travel limitations. The Winecoff Hotel fire article (which I wrote) discusses some of the improvements to stair arrangements and protection brought about by that tragedy.   Acroterion   (talk)   04:57, 25 January 2013 (UTC)


 * It bears mentioning that the event, in the U.S., that led to widespread fire safety practices in terms of building design as well as even things like "fire drills" is the Triangle Shirtwaist Factory fire. -- Jayron  32  17:23, 23 January 2013 (UTC)
 * Since outsourced to Tazreen Fashion... Wnt (talk) 02:00, 24 January 2013 (UTC)

Barter prices for iron in ancient and medieval times compared to other goods
I wonder what the price of, say, a pound of iron was back in history in different places, compared to other goods, like grain, wine, copper, silver, gold, shoes, clothes or different kinds of livestock. 93.132.137.91 (talk) 19:07, 22 January 2013 (UTC)
 * I doubt that it was bartered very much. It's really only directly useful to a blacksmith, and doesn't make a very convenient medium of exchange.  The amount that a blacksmith would give in barter would depend tremendously on supply and demand as well as on the quality of the iron. Looie496 (talk) 19:35, 22 January 2013 (UTC)


 * I wonder if you will get better information at the Humanities desk, because there are more qualified historians who would know how to look for such an answer. I assume, for example, that there is much recorded history of trade and merchant transactions, including prices, dating back to the economy of the Roman empire, who were notorious for writing down everything.  We've got Roman_economy; Roman_metallurgy; those should point you in the right direction, at least!  Certainly, data is known about the economies of other historical empires whose records are well-studied.  The farther back into the bronze-age and beyond, the harder it is to know with great certainty; but again, the humanities desk may contain more archaeologically-interested contributors who would point you to good resources.  Nimur (talk) 19:46, 22 January 2013 (UTC)


 * I'm not sure about that. As I have started the question here I would like to see what answers I can get here first, before moving or duplicating the question. 93.132.137.91 (talk) 19:58, 22 January 2013 (UTC)


 * (after ec);
 * I was asking for "barter" because I don't want those studies that try to give values in modern day currencies. Those are frequently in the media, telling that an average worker in some underdevelopped country gets only half a dollar per day, neglecting that he can buy from that, on average at least, enough to make a living for him and his family. Which wouldn't be possible from ten times the income in any "developed" county. So when I said "barter", I meant "what could he get in exchange".
 * The picture from the article Bloomery lets me guess that the gain from one bloom was at least enough to have a days meal for several people. 93.132.137.91 (talk) 19:52, 22 January 2013 (UTC)


 * It might, perhaps, be possible to get an idea of the cost by comparing the barter value of iron objects made by a blacksmith and figuring some kind of cost he'd add for his labor. Horseshoes ought to be a good thing to consider.  But money was pretty well established in those times - it's not clear whether they'd still be bartering anyway. SteveBaker (talk) 20:44, 22 January 2013 (UTC)
 * Iron was also used to make coins in a number of times and places as was lead, copper, silver, gold. So it may have been more like bullion than barter. Rmhermen (talk) 20:50, 22 January 2013 (UTC)
 * From the discussion above (Trip hammer mechanics) it was mentioned that the Obol (coin) represents a certain amount of iron - literally translated as a "handful" of iron rods. From the article: grasp of six oboloi [handful of iron rods] = 1 drachma.  I'm not sure what 1 drachma could buy - perhaps a large pizza and a pitcher of beer? ~:74.60.29.141 (talk) 21:05, 22 January 2013 (UTC)


 * I don't think that insisting on barter is necessarily more instructive. The Roman Empire had a well-defined currency system, and prices related to it are moderately well-known. If you don't want unhelpful modern-day conversions, just ask the humanities desk for prices in denarii, etc. AlexTiefling (talk) 21:08, 22 January 2013 (UTC)

OK I see my original question was somehow misleading. So I rephrase it. In different times and locations, especially non-modern (medieval, ancient, iron-age), what kind of living could I buy for me (and my family) if I produced an iron bloom every day, week, month? 93.132.137.91 (talk) 21:30, 22 January 2013 (UTC)
 * "55 pounds of grain (1 medimnos) cost 5 drachmas 7" -and- "Greek rowers on triremes in the 5th century also earned 1 drachma/day" :  (do the math)   ~:74.60.29.141 (talk) 21:35, 22 January 2013 (UTC)
 * The problem is determining how much weight ≃ 6 iron "rods", which ≃ about 10 lbs grain, ≃ one day's labor wages, etc. (and what is an "iron bloom" worth?).~:74.60.29.141 (talk) 22:01, 22 January 2013 (UTC)
 * It is not only that I am too lazy to do all the math, and it is not only that this would be ill famed original research, but I think that there are (or at least should be) some resources out there on the net from some people who have already done such research (and who have very probably been paid at least indirectly from some money taxed from other people). Anyway, there is probably some already existing knowledge that is easier to improve than to start all over again each by oneself, and based on indirect data randomly found. 93.132.137.91 (talk) 22:22, 22 January 2013 (UTC)
 * Right, that "already existing knowledge" is called "history," and it is typically classified as a humanities. The resources out there, on the net and elsewhere, are called "historical documents" and "secondary sources" that regurgitate such knowledge in more digestible forms.  And, the "people who have already done such research" are called "historians."  This is not meant to sound snarky; I'm trying to be sincerely helpful here: this is a realistic acknowledgement that the best answers for this type of question will probably be found on the Humanities reference desk, because it is full of people who are on the whole better able to find and interpret such resources.  Nimur (talk) 22:39, 22 January 2013 (UTC)
 * So I will, after some waiting here, repost the question on the Humanities desk. But don't think of me as all too lazy .... if you try a google on "prices historical" you get a real lot of hits about stock market prices reaching back even as far as ten years. But not really what I am looking for.  93.132.137.91 (talk) 22:45, 22 January 2013 (UTC)

Discourses on Salt and Iron (81 B.C.) is an interesting book about this subject. -- Toytoy (talk) 17:23, 23 January 2013 (UTC)

Help me identify an insect


Any idea what this is? It's sitting in my bathtub; I live in the woods near Bloomington, Indiana. When I took the photo (which I've cropped from 2816×2112 pixels), a human hair was sitting next to it; when I went back a few minutes ago, the hair was gone despite no other changes; I wonder if it might have eaten the hair. It's almost exactly an inch long. Note that the thing appearing to protrude from the rear of the insect is actually a line on the tub, not a part of the insect. Nyttend (talk) 19:50, 22 January 2013 (UTC)


 * As for eating hair, I believe cockroaches will do that, so it's possible this critter did, too. StuRat (talk) 19:55, 22 January 2013 (UTC)


 * Looks to me like your basic oriental cockroach. It's not uncommon for them to come out of drains. Looie496 (talk) 20:23, 22 January 2013 (UTC)
 * Uggg...time to talk to the landlord, I guess. I wondered about a roach, but (1) I thought cockroaches fled from light, while this sat still although the ceiling light was on for more than a full minute, and (2) I thought cockroaches lived in warmer climates.  Nyttend (talk) 21:05, 22 January 2013 (UTC)
 * Cockroaches live almost everywhere... they just start approaching the size of small pets when you go into warmer climates. Shadowjams (talk) 15:13, 23 January 2013 (UTC)


 * If it's what I think it is, there's no need to talk to the landlord. These are known as "sewer roaches" -- they don't move very quickly, and don't give rise to infestations -- they just occasionally make their way up from the sewer where it's warm.  They're nasty because they're large and ugly, but they aren't nearly as much of a problem as the smaller American and German cockroaches. Looie496 (talk) 21:10, 22 January 2013 (UTC)


 * I have found that keeping a jug of bleach handy and giving the drain a small splash of it after using the tub or shower keeps them out and also avoids the drain getting smelly. A stopper would also work.


 * For the Germans and Americans, a combination of Dupont Advion roach bait, Gentrol Point Source IGR Insect Growth Regulator and Harris Roach Tablets works wonders. The Gentrol stops the next generation from growing up, the Advion gives you secondary and tertiary kills (Google it - it's disgusting) and The Harris Tablets are non-toxic (boric acid) and so cheap you can throw one in every drawer and every cupboard shelf, behind every appliance, etc. --Guy Macon (talk) 23:10, 22 January 2013 (UTC)

Unknown plant
Anyone know? M.t.lifshits (talk) 20:45, 22 January 2013 (UTC)
 * Expanded.-- Gilderien Chat&#124;List of good deeds 20:49, 22 January 2013 (UTC)
 * I'm getting euphorbia vibes, but couldn't say what variant. Looie496 (talk) 21:01, 22 January 2013 (UTC)
 * It grows in a pot, and not have irrigation, only rain. M.t.lifshits (talk) 21:24, 22 January 2013 (UTC)
 * It certainly has a superficial likeness to Euphorbia characias "Portuguese Velvet",(aka Spurge, Portuguese Velvet) the stems look very euphorbia-like. If you can pull off a leaf stalk and cut or break it, if it is a euphorbia it will have a definite milky sap, CAUTION - this sap can badly irritate some people's skin so take care. Euphorbias are usually drought resistant which this plant seems to be. Richard Avery (talk) 22:54, 22 January 2013 (UTC)
 * Thank you very much. M.t.lifshits (talk) 08:42, 23 January 2013 (UTC)