Wikipedia:Reference desk/Archives/Science/2016 August 1

= August 1 =

Why'd the box my bear spray shipped in have this end up stickers?
The can doesn't say that. Then again the can also doesn't say anything about spraying the can upside down which would seem more likely to get you eaten (but what do I know, maybe it'd work upside down but if so that'd make the "this end up" stickers even more pointless). Sagittarian Milky Way (talk) 01:05, 1 August 2016 (UTC)


 * We don't know what sort of box your bear spray was shipped in. It it was more loosely closed at the top, for example, keeping it "this end up" would reduce the chance of the contents spilling out. --69.159.9.219 (talk) 03:47, 1 August 2016 (UTC)
 * The can has a "mechanism" on the top of it. It's individual packaging probably protects it to a degree, but it's still probably better for the cans not to be shipped upside down. Jiggled around, knocked about, picked up and dropped. Possibly the contents settle to some degree at the top of the can making the first few seconds of spray less optimal. It might be mostly just a precaution. When i send a package, I usually put "fragile" on it even if what I'm sending isn't' particularly fragile.   Vespine (talk) 04:44, 1 August 2016 (UTC)
 * If a spray can inside a cardboard box is dropped upside down, it may discharge part of its contents, creating a messy and possibly hazardous situation. I sometimes get shipments of granite sealer labeled the same way, since the containers can leak a bit if dropped upside down. Cullen328  Let's discuss it  05:14, 1 August 2016 (UTC)
 * A guess only: The expenses for shipping hazardous goods are extreme, if carriers are willing to handle them at all, and getting goods exempted, or getting shippers to handle them, depends a lot on convincing them that they are really, really safe.  Firefighters don't want to respond to a wreck and get hit with bear spray!  Inevitably shipping a box will be at least marginally safer, in case of a major traffic accident or any other disaster, if it is in one orientation than another.  Hence the sticker.  Someone still has to look up how canisters of bear spray are placarded, but there's a chance the OP knows this already from paying the shipping charges. Wnt (talk) 13:04, 1 August 2016 (UTC)
 * Just a guess but perhaps the propellant leaks out slowly when it is upside down? There may be a tube which goes to the bottomof the can and if it is upside down it would be in the propellant rather than the bear spray mixture. Dmcq (talk) 15:01, 1 August 2016 (UTC)
 * Does the company perhaps sell other products for which the orientation precaution might be appropriate? If so, they may routinely label their boxes this way. Such labeling also encourages the consumer to open the box from the top, rather than from the bottom. This could be helpful if literature or an invoice is to be encountered upon first opening a shipped box. Bus stop (talk) 15:15, 1 August 2016 (UTC)
 * At least one Canadian shipping company appears to require orientation labels for all aerosols they will ship except for those which qualify as limited quantity which doesn't include anything sent by air (although bear spray is probably only allowed on cargo aircraft ) . Admitedly this document possibly from the UNECE doesn't seem to require orientation arrows for aerosols but I guess some do. It's also possible the container it was shipped in has an orientation for some reason e.g. vents (well that seems unlikely), adsorbent material, protection e.g. I imagine this very large one does . Nil Einne (talk) 17:56, 1 August 2016 (UTC)

In our body > basic becomes acidic and vise versa?
Is that true that every acid that comes in our body becomes to basic, and every basic that comes in our body becomes to acid? (for example if we drink or eat acidic or basic food or drinks)194.114.146.227 (talk) 05:54, 1 August 2016 (UTC)
 * Well, I'm sort of struggling to figure this question out. I could be missing the mark here, but I do not believe this is any kind of biological principle. If you add something that is acid to something else which is not as acidic, it will become "more basic", and conversely if you add a strong base to something not so "basic" it will become "more acidic". Blood is close to neutral, at a pH of about 7.4 so presumably if you consume anything more acidic than that, it will become less acidic and if you consume something more basic than that it will become less basic, in the short term, everything you eat takes a trip into your stomach which has very acidic contents, at a pH of about 2. I'm guessing you could consume something so basic it will kill you, but in the process it will still become "more acidic", does that still satisfy your condition? Vespine (talk) 06:29, 1 August 2016 (UTC)
 * This "basic/acidic" stuff is just so much "natural medicine" bullshit -- the truth is, the human body is highly buffered, so no matter what you eat, your body's pH changes are negligible! (Which is a good thing, because even a 0.5 change in your body's pH could kill you!) 2601:646:8E01:7E0B:F88D:DE34:7772:8E5B (talk) 10:36, 1 August 2016 (UTC)
 * For more information on abnormal pH, our articles are Acidosis and Alkalosis, as well as Acid–base imbalance.
 * While I agree that there is a lot of pseudoscientific "alternative medicine" nonsense that tries to apply these concepts, pH balance is a real thing, and imbalance can represent a real medical problem. For example, if you are the sort of person who regularly breathes an artificial atmosphere - like a SCUBA diver or an aviator - you ought to be aware that respiratory acidosis is a real thing, and is often a symptom that you are not receiving enough oxygen (or you're getting too much carbon dioxide) in your breathing gas.  Our article lede calls this pH imbalance event a "medical emergency" - and it surely can be.
 * Interestingly, connected to the earlier discussion about blood-typing, I found that my local blood center disrecommends both aviation and SCUBA after donating blood - that's probably more out of concern for anemic hypoxia due to loss of red blood cells; but anything you do that messes with your blood equilibrium will surely have many profound effects on your overall cardiopulmonary health.
 * And, in this fascinating issue of The Federal Air Surgeon's Medical Bulletin, High Altitude Flying in the Andes Mountains, a medical doctor discusses research into the prescription of Acetazolamide as a prophylactic against acute mountain sickness ("altitude sickness"). The drug intentionally induced acidosis, with the objective of inducing hyperventilation (..."Acetazolamide is a carbonic anhydrase inhibitor that forces the kidneys to excrete bicarbonate, making the blood more acidic. This metabolic acidosis stimulates minute ventilation, increasing oxygen in the blood...").  A fascinating reported side-effect was "aversion to carbonated beverages."
 * Nimur (talk) 16:12, 1 August 2016 (UTC)
 * Indeed, thank you for finding that interesting paper! DMacks (talk) 16:34, 1 August 2016 (UTC)


 * Acid and base seem conserved in the lab, but they don't seem conserved in the body. There are a bunch of reasons for this, but one of the key ones is that the body is continually emitting carbon dioxide, which in water is carbonic acid.  In the lab, a container of sodium hydroxide remains sodium hydroxide because it is tightly capped on the shelf; but carbon dioxide can seep in if it is poorly sealed and gradually turns it into sodium bicarbonate, which is only mildly alkaline.  Because food is generally destined to be turned into CO2, with frequent exceptions, the outcome from an acidic or a basic food seems hard to predict.  But in an alkaline diet, some things like citric acid seem to star prominently. Wnt (talk) 18:43, 1 August 2016 (UTC)