Wikipedia:Reference desk/Archives/Science/2017 November 5

= November 5 =

Burqan 2 ballistic missile spesifications?
All over the news today is the claim that Saudi Arabia shoot down a Burqan 2 ballistic launced from Yemen. I have looked, but fail to find much of anything about the Burqan missile; who made/makes it, spesfication, design lineage, anything. Do anyone have any pointers or know of any resources on this missile? WegianWarrior (talk) 11:12, 5 November 2017 (UTC)
 * See Volcano H2 for our article. Perhaps some redirects need to be created. Tevildo (talk) 12:04, 5 November 2017 (UTC)
 * Thank you :) WegianWarrior (talk) 16:45, 5 November 2017 (UTC)
 * I have now created 3 redirects with variations as used by news broadcasters. Graeme Bartlett (talk) 21:05, 5 November 2017 (UTC)

Deodorant Manufacturing Process
How does a Deoderant remove foul odors? Is it activated Carbon which is used to absorb foul odors? — Preceding unsigned comment added by 117.194.220.156 (talk) 13:40, 5 November 2017 (UTC)
 * I think our deodorant article explains it in a reasonably clear way. Looie496 (talk) 13:56, 5 November 2017 (UTC)
 * Are you referring to body deodorants? Here is an article talking about how body deodorants work. Also see body odor. Bus stop (talk) 13:57, 5 November 2017 (UTC)


 * Personal anti-perspirants work by applying an astringent to the skin pores, thus reducing perspiration. Most body odour develops from bacterial action on stale perspiration. These are usually aluminium based, often based on alum (a common one in some countries is just rubbing an alum block over the skin). In the West, "aluminium free" anti-perspirants are sold by fashionable fools and charlatans when these are made from alum (which of course, contains aluminium).
 * Deodorants for personal use are mostly perfumes which camouflage odours, although often include anti-perspirants and some include biocides to try and reduce the skin bacteria. Some, like Lynx (UK) / Axe (US) are so powerful and generally unpleasant that they have become known as the smell of male teenagers. The phrase "Glasgow shower" (other despised neighbouring towns are available) refers to the practice of never washing, but merely spraying on another layer of artificial smell. Trying to remove skin bacteria is often not a good strategy: skin will have a colony of some bacteria, and removing the benign ones may encourage a worse group to predominate. Also the usual problem of antibacterial resistance can develop.
 * For cleaning fabrics, adsorbants are used, and have been used since ancient times. They aren't used on the body as they'd leave dust behind. Activated carbon isn't used on fabrics, because it would leave ingrained black dust behind, but fuller's earth is. A modern and more powerful version of this are the odour eliminators such as Febreze which are based on cyclodextrin molecules.Andy Dingley (talk) 14:32, 5 November 2017 (UTC)
 * Most Deoderant's simply use Salt to "paint" a zone with it which makes it inhospitable for the bacteria which naturally thrive on your sweat and dead skin cells and thereby produce the smell as waste product. So deodorants dont remove smell, they try to prevent it. Also deodorants often additionally contain perfume to make customers happy and secure of themselves. So you can make your own deodorant for a few pennies instead of buying the very expensive salt-based "beauty products"! Go try! --Kharon (talk) 14:48, 5 November 2017 (UTC)
 * What do you mean by "salt" here?  Common table salt, sodium chloride?   In which case, no they don't. Andy Dingley (talk) 15:00, 5 November 2017 (UTC)
 * He means Aluminium chlorohydrate. In chemistry, a Salt is any ionic electrolyte.  -- Jayron 32 14:54, 7 November 2017 (UTC)

Note that the correct spelling is deodorant. It's misspelled by two editors above. Akld guy (talk) 15:50, 5 November 2017 (UTC)

what is the nuclear reaction that occurs in radiation therapy?
? — Preceding unsigned comment added by 107.77.226.41 (talk) 20:39, 5 November 2017 (UTC)
 * Radiation therapy is the place to start reading, assuming you you mean what does the radiation do, not how is the radiation produced. DMacks (talk) 20:47, 5 November 2017 (UTC)
 * The short takeaway is that, at least for the primary mode of action, no nuclear reaction is involved at all. The particles create ionization (see ionizing radiation), which then acts chemically, not at the nuclear level. --Trovatore (talk) 20:50, 5 November 2017 (UTC)
 * Sorry to mince words - but a radioactive source is undergoing a nuclear reaction, all the time. It  just happens to be a slow, low-energy reaction, when we compare it to a textbook Uranium-235-esque fission chain reaction.  I am not qualified to say "why" a nuclear reaction can aid in medical treatment, but as Trovotore has correctly pointed out, there are many messy details pertaining to the secondary actions of the ionized particles, and subsequent chemical and biological effects.  In my opinion, "almost nobody" knows if - or how - this works - but it is nonetheless an accepted medical practice in some parts of the world.
 * Most radiation therapy involves exposing a patient to a material - like fluorine or iodine - that undergoes a beta-decay reaction, in the hope that the emitted particles will have a helpful effect on the patient's ailment.
 * There is also an entire field of nuclear medicine that is much larger in scope than just radiation-therapy. Medical practitioners and researchers employ all sorts of nuclear physics to perform diagnostics and to treat patients.  For example, positron emission tomography uses beta-decay (positron emission), a nuclear reaction, to "light up" the insides of a patient during medical imaging.  In fact, it is more common to use nuclear medicine for diagnosis, rather than for treatment.
 * Using nuclear medicine for therapy - inverventional nuclear medicine - typically involves intentional exposure of the patient to a radiological source.  Several methods are listed in our article.   Almost always, the radiological source is iodine, fluorine, or barium, which all naturally undergo the nuclear reaction called "beta decay."  Our article lists several other materials. The actual materials that get used depend on the patient's condition, the doctor's choices, and availability and regulation in various parts of the world.
 * I am aware of at least a few places in the world that use "other" nuclear reactions: for example, neutron exposure, and even muon beam radiotherapy. Both of these methods are extremely uncommon: in fact, all interventional radiotherapy is "pretty uncommon," but the more esoteric the particle (like the mild-mannered neutron or muon!), the less likely that a well-credentialed practicing clinical cancer doctor will have the means or the motive to choose to employ it.  It is comparatively easier for a clinician to obtain and prescribe radiological medicine like iodine: if the clinician wants to use a neutron source for therapy, they need a special machine in a special facility.  Very few of these machines exist, in low single-digits, worldwide - so the patient would have to be referred to an extraordinarily special oncology/nuclear-medicine research clinic.
 * (Side note): I'm participating in an online refresher-class, titled "Dr. Bill Perry and Valerie Plame induce further informed but unhealthy paranoia about nuclear technology," or something like that - so, part of me wants to shout out into the hypothetical void: "what the heck is a so-called oncologist doing with a slow neutron source in South America anyway, selling it?" ... but I'm drifting off topic.
 * In layman's terms -
 * Most of what we call "nuclear medicine" is diagnostic ("putting the patient in a special type of X-ray machine for a few minutes"); and if the doctor decides to go farther, the majority of interventions ("giving the patient a dose of something") involve exposure to light isotopes undergoing natural decay - like iodine beta-decay - frequently in the form of a pill, a suppository, or an injection.
 * Nimur (talk) 15:27, 6 November 2017 (UTC)


 * You seem to have largely omitted radiosurgery which is a form of interventional radiation therapy (usually using gamma rays) that is now widely available. Dragons flight (talk) 18:57, 6 November 2017 (UTC)
 * Indeed, that is yet another form of nuclear medicine and it appears to be in widespread use. Nimur (talk) 19:48, 6 November 2017 (UTC)

Which fungi species are in US food?
In the European Union, the species of mushroom in a food product have to be declared, I think.

According to producer information, the product "Lipton, Recipe Secrets, Recipe Soup & Dip Mix, Onion Mushroom" contains :


 * "Mushrooms* A type of fungi consisting of a stalk with an umbrella-shaped cap. Growing Method Conventional Farming Country of Origin China / India Ingredient descriptions have been provided by Lipton"

Is there a way to find out which exact species of fungi or mushrooms are used in this or other products sold to consumers in the USA? Rosenkohl (talk) 22:28, 5 November 2017 (UTC)
 * Cheap food mushrooms are Agaricus bisporus, but that doesn't actually help that much, because there are some quite distinct cultivars within that. Most of the "mushrooms" you see in a British or US supermarket are this species, including globular white button mushrooms, large flat "field" mushrooms, brown chestnuts, large portabellos and small portabellini. If you find collected flat white mushrooms in a market, rather than farm cultivated, they may be Agaricus campestris (the real "field" mushroom) instead, but these aren't grown intensively.  In mainland Europe, of course the range is vast and most that are edible, are collected and eaten.
 * As a wild guess from knowing mushroom growing, mushrooms for flavouring like this are usually the small white button mushrooms (as the fastest growing) and may be the stalk trimming after the caps have gone for more visibly decorative uses, such as pizza toppings.
 * Also, just ask Liptons. Andy Dingley (talk) 23:33, 5 November 2017 (UTC)
 * Your premise about the mushroom species having to be declared in the EU seems to be mistaken: Tesco Cream Of Mushroom Soup 400G (UK) only says " Mushroom (6%)" and Carrefour Soup Crème de Champignons avec Morceaux 460 ml (France) says "champignons 10%". Alansplodge (talk)


 * In the United States, you can also find Tremella fuciformis (colloquially known as the silver ear fungus, which is translated literally from the Chinese term). There is also Auricularia auricula-judae (colloquially known as the wood ear, also translated from the Chinese term literally). You find these in Asian-American supermarkets, though. SSS (talk) 02:41, 10 November 2017 (UTC)
 * You can find lots of fungi for sale. They won't be sold as merely "mushrooms" though. Even fairly commonplace morels, boletes or shiitakes will be upsold as "wild" or "forest" mushrooms. Andy Dingley (talk) 20:00, 10 November 2017 (UTC)