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July 5

Scientifically, is it possible to improve IQ score?

Scientifically, is it possible to improve IQ score? Or what human have it's constant for him forever, no matter what he does to improve it? --2A02:ED0:6D6D:F300:7869:435F:5ED7:13CC (talk) 13:09, 5 July 2018 (UTC)[reply]

See Intelligence_quotient#Interventions. Ian.thomson (talk) 13:12, 5 July 2018 (UTC)[reply]

See Flynn effect. IQs are on the rise for society as a whole. Section 3 of the article gives several possible explanations for this increase. --Doroletho (talk) 14:44, 5 July 2018 (UTC)[reply]

If you look further you'll see there is some evidence the effect is ending or has ended and IQs are now decreasing if anything. Dmcq (talk) 11:21, 6 July 2018 (UTC)[reply]

In any event, Doroletho has conflated two questions here. The Flynn effect is about a general rise of IQs in large segments of contemporary populations, whereas the OP was asking if it is possible for an individual to improve their score. The answer there is yes and no. IQ tests remain tests even if they are more predicated in generalized problem solving than in the application of a particular knowledge base, so familiarity with the particular cognitive exercises and analytical problems any particular IQ test employs will improve facility with those tasks. So one who gains familiarity with a particular kind of IQ test can leverage marginally improved scores. However, this does not necessarily equate to an actual increase in IQ.

The answer to the OP's inquiry also varies a bit by particular test. IQ is a funny thing, because we don't really have a firm definition for it that is abstractly descriptive, only a statistical argument for its empirical existence. Modern cognitive science is divided as to validity of a strong g factor (that is, a a statistical observence of a correlation between aptitude between different cognitive tasks) but even its strongest proponents are unlikely to believe there is such a thing as strict "general intelligence"; we now recognize the multiplicity of mental tasks is so great, that any application of psychometrics is always going to be limited with regard to the scope of the conclusions which can be reached as to general intelligence. But yes, previous testing (and I will try to find the sourcing shortly) has demonstrated improvements to score on many historical IQ tests can be improved--up to a point where scores will plateau, of course. Snow ^{let's rap} 11:17, 8 July 2018 (UTC)[reply]

My mother was a schoolteacher and administered several tests. She would also (in between crosswords and knitting) solve the papers for herself. So on an IQ test (or at least, the Cattell tests she was familiar with) she could regularly nail a 180+ score. Now she was smart, but not that smart. Andy Dingley (talk) 17:12, 5 July 2018 (UTC)[reply]

The article here on wiki is not clear in the light of these answers. --2A02:ED0:6D6D:F300:7869:435F:5ED7:13CC (talk) 00:42, 6 July 2018 (UTC)[reply]

Why not?? My mother did one of those societies tests and got 165 and one of my sons 183 so it certainly isn't unreasonable. Dmcq (talk) 11:30, 6 July 2018 (UTC)[reply]

Subjectively I'd say a person's cognitive ability can vary with their health, diet, mental outlook, and all sorts of other things. Exercise and mental stimulation count for a lot. 173.228.123.166 (talk) 08:23, 8 July 2018 (UTC)[reply]

Indeed. Also, for some live tests, the competency of the psychologist is a factor. Moreover, people tend to do much better at particular tests (and usually do better at the same test the second time). Although most tests attempt to properly distribute different problem types, they aren't exact science and the balance may not fit everyone. Assessing intelligence is not an easy problem... To answer the original poster: yes, one can do better with some research (into popular test types) and practice (playing related games). —Paleo Neonate – 11:42, 8 July 2018 (UTC)[reply]

Measles

This news article about a measles case in Portland says, "A person is considered immune to measles if they were born before 1957, had the measles previously, or have been fully vaccinated for measles." How does being born before 1957 afford immunity? Is this just a poorly worded sentence based on the assumption that most people born before 1957 are immune because they are likely to have gotten measles in their childhood? (In this case, the sentence would be more accurate if "were born before 1957" were simply removed from the sentence.) ANDREVV (talk) 13:20, 5 July 2018 (UTC)[reply]

It's because they will have lived through several epidemics and so are likely to be immune see [1] Richerman (talk) 14:28, 5 July 2018 (UTC)[reply]

The year is included because it is the date at which the (U.S.) Centers for Disease Control and Prevention advise that people do not need the measles vaccine booster - Nunh-huh 16:11, 5 July 2018 (UTC)[reply]

When 20 is not the double of 10 in a scale

How do you call a scale like Celsius, in which 20 degrees is not the double of 10? Or SPF, where SPF 30 does not protect 50% more than SPF 20? --Doroletho (talk) 14:36, 5 July 2018 (UTC)[reply]

Celsius is a relative temperature scale with arbitrary reference points, conventionally 0 °C and 100 °C for the freezing and boiling temperatures of water. One may however convert a Celsius reading to Kelvin using [K] = [°C] + 273.15. The Kelvin scale is absolute so "twice the Kelvin" means "twice as hot".

SPF (Sun Protection Factor) is a reciprocal expression of the fraction of sunburn-producing UV rays that a Sunscreen allows to reach the skin. For example, "SPF 15" means that 1⁄15 of the radiation reaches the skin, or conversely that one may sunbathe 15 times longer with the same risk of burn as without the sunscreen. SPF 30 should allow 50% longer sunbathing than SPF 20. DroneB (talk) 16:55, 5 July 2018 (UTC)[reply]

Our article Level of measurement explains the relevant concepts. It distinguishes four types of scale: nominal, ordinal, interval, and ratio. Celsius is an interval scale. SPF is a ratio scale. Looie496 (talk) 17:15, 5 July 2018 (UTC)[reply]

So in the terminology of that article, the answer to the question is "it's not a ratio scale". However, note that SPF is a ratio scale: SPF 30 does protect 50% more than SPF 20, if everything else is equal.

However, while I don't imagine that the authors of the article made it up, I do not think this "ratio scale" terminology is widely used. I read quite a bit about units of measurement and I don't remember ever hearing of it before. --76.69.47.228 (talk) 02:09, 6 July 2018 (UTC)[reply]

IP is correct. See Level of measurement. The terms you are likely looking for are nominal, ordinal, interval, and ratio scales. Nominal scales are things like gender, religious affiliation, or race. Ordinal scales are ones that can be ordered from most to least or largest to smallest, like likert scales, but the distance between each value is unknown. Interval scales are rather uncommon but examples are Fahrenheit and Celsius and dress sizes. They are like ordinal scales butt the distance between each value is known to be equal. However, they do not have a true zero value. Ratio scales have all the attributes of interval scales but have a true zero value. An example would be the Kelvin scale. EvergreenFir (talk) 02:15, 6 July 2018 (UTC)[reply]

That's my take too; even in the Kelvin scale you can't say "twice as hot". There'd have to be a scale based on the average velocities of the particles. Abductive (reasoning) 23:07, 6 July 2018 (UTC)[reply]

As an aside, I've been following this thread and find it very intriguing/educational. Thanks to all who've participated, even though I'm not the OP! Killiondude (talk) 23:21, 6 July 2018 (UTC)[reply]

I've heard of million, billion, trillion, etc. How many is a killion? ←Baseball Bugs ^{What's up, Doc?} carrots→ 01:52, 7 July 2018 (UTC)[reply]

Unless I'm misunderstanding the question, any logarithmic scale fits the description. Most commonly used ones are base-10 logarithmic, meaning each level on the scale represents a power of ten. A pH of 5 is ten times more acidic than a pH of 6, and so forth. --47.146.63.87 (talk) 06:41, 7 July 2018 (UTC)[reply]

I would use this mathematical terminology: 20 degrees celsius is not "double" the temperature of 10 degrees celsius, because the Celsius scale has a bias. In this sense, a bias is an offset added to a linear equation; bias is the "b" term in the common notation "y = mx + b. In the case of Celsius, that bias yields the difference between the Celsius scale and the Kelvin scale; its value is about 273.15; it is no coincidence that it relates to the value of absolute zero when measured in Celsius.

In particular, the linear equation here is the one that defines temperature (in celsius) as a function of the average kinetic energy in the molecules of a sample. It is a simple algebraic rearrangement of the definition of thermodynamic temperature, by solving for T, and biasing for the units in Celsius.

This is categorically different from some of the other explanations presented in the earlier discussion, because the scale is linear, not logarithmic or exponential or anything else. It is for this reason that a 10 degrees celsius difference is related to the same amount of change in heat energy: it takes the same amount of fuel ("ΔQ") to cook water from 10-to-20 °C as we require to cook it from 20-to-30 °C, or from 80-to-90 °C. These temperatures represent linear increases in the heat energy added to a sample; and, because of the scale's bias, zero celsius does not mean zero energy is contained in the sample.

Nimur (talk) 15:18, 8 July 2018 (UTC)[reply]

Celsius temperature is an affine function of absolute temperature, not a linear one. 173.228.123.166 (talk) 15:22, 8 July 2018 (UTC)[reply]

This is true; I do not disagree. An equation can be expressed as a linear polynomial; this is a different mathematical statement than saying that the system is linear. Quoting our article:

"Note that this usage of the term linear is not the same as in the section above, because linear polynomials over the real numbers do not in general satisfy either additivity or homogeneity. In fact, they do so if and only if b = 0. Hence, if b ≠ 0, the function is often called an affine function (see in greater generality affine transformation)."

For this reason - to expound on the subtle details! - mathematical physicists usually study linear systems for at least a half a year during their formal education. Here was the book I used: Haykin & Van Veen, Signals and Systems (2003). The first two hundred pages are on various definitions, and properties, of linear equations and linear systems; the most important properties are superposition and homogeneity.

We might say that energy and temperature satisfy a homogeneous linear relation if we measure temperature in Kelvins, but not so if we measure in Celsius.

The original question was about terminology used to describe different scales of measurement; suffice to say, the more terms you know, the more precisely you can describe the details - at the risk of losing the audience in domain-specific jargon that sounds an awful lot like technobabble-nonsense!

Nimur (talk) 15:31, 8 July 2018 (UTC)[reply]

Children of homosexual couples.

I recently came across an entry for Linda Perry. In her personal section it says her wife gave birth to their child. This seems to imply that biologically something happened. I do realize that this is a sensitive topic, however, for accuracy wouldn't it be more appropriate to specify surrogacy (or another method?) There may come a time where science allows for a biological child, but for now it is technically incorrect to state or imply that this child belongs biologically to both partners

https://en.wikipedia.org/wiki/Linda_Perry

https://en.wikipedia.org/wiki/Sara_Gilbert — Preceding unsigned comment added by 24.144.1.3 (talk) 17:31, 5 July 2018 (UTC)[reply]

This comment belongs on the article’s talk page, not here where the purpose is to request references. Loraof (talk) 19:27, 5 July 2018 (UTC)[reply]

This is addressed at Talk:Sara Gilbert#Parentage. -- ToE 07:53, 6 July 2018 (UTC)[reply]

Just to use the opportunity to educate the IP as to our policies though, I will note that the comments in that stale discussion are pretty off-base in terms of WP:Verification and WP:NPOV. The reason that it is permissible to mention the child as that of the couple is only indirectly connected to the legal, social, and common sense reasoning expressed on that talk page. As solid as some of those arguments are in various regards, they represent WP:original research just as much as the edit summaries of the IP who tried to remove that description in the first place. We don't use our own rational conclusions (however certain we are about them) to define how we describe people (or any topic) in our content, in Wikipedia's voice. The reason we need to describe the child as that of the couple is because that is how the sources describe the child and the relationship to his mothers (plural). For more information, OP, please see WP:WEIGHT. Snow ^{let's rap} 11:26, 8 July 2018 (UTC)[reply]

July 6

Why soda (Sodium bicarbonate) isn't considered as anti acidic drug?

There are many antacids drugs, but my question Why soda (Sodium bicarbonate) which anybody consumes it as a carbonated water form isn't considered as anti acidic drug? According to my logic, soda is base and base is antacid. Isn't it? --2A02:ED0:6D6D:F300:7869:435F:5ED7:13CC (talk) 00:46, 6 July 2018 (UTC)[reply]

The drink "soda" is likely to have no sodium bicarbonate in it. The carbon dioxide will be partly in the form of carbonic acid which then might make a tiny amount of bicarbonate as it ionises. But this is balanced by the hydrogen ions, so it is not classified as a base, but more as an acid. I won't comment on drug classification as to antacid use. Graeme Bartlett (talk) 02:03, 6 July 2018 (UTC)[reply]

Not true. Many of them do have sodium bicarbonate: See here for example (club soda ingredients of schweppes). 188.120.129.140 (talk) 15:09, 6 July 2018 (UTC)[reply]

And here is a listing of pH values for a number of popular non-alcoholic, non-dairy drinks. You'll note that almost all of them have pH<7.0, i.e. are acidic. Abecedare (talk) 02:17, 6 July 2018 (UTC)[reply]

Some soda water has potassium carbonate added, whihc would be in the form of potassium bicarbonate once carbonated. Also there are mineral waters with calcium bicarbonate or magnesium bicarbonate in solution. Graeme Bartlett (talk) 03:55, 6 July 2018 (UTC)[reply]

Magnesium salts cause diarrhea don't they? And another one maybe aluminum causes constipation. So if the OP wants a cheap antacid that should be taken into consideration (and that the cheapest chemicals would have impurities that might make them unfit for human consumption. I'm not sure if reagent grade is pure enough to be sure it's food grade if the chemical you're getting 99.99x% of is even safe to eat in antacid quantities in the first place. Also some bases are too strong to eat without great dilution. i.e. Sodium hydroxide is a base and that article has a photo showing that it eats organic tissue without a lot of dilution. This is also why wet cement itches (alkalinity) cement is not a good antacid obviously) Sagittarian Milky Way (talk) 06:02, 6 July 2018 (UTC)[reply]

Almost no one in richer countries is short on sodium and lots of people eat too much. That's probably why. Sagittarian Milky Way (talk) 02:37, 6 July 2018 (UTC)[reply]

And sodium bicarbonate isn't generally a major ingredient in soda drinks for enjoyment because too much would add saltiness. Perhaps someone is selling some sodium bicarbonate water somewhere to drink as a "keep healthy" or dubious remedy for something but it probably wouldn't taste good or sate your thirst if it has enough sodium bicarbonate to use as an antacid. Sagittarian Milky Way (talk) 02:45, 6 July 2018 (UTC)[reply]

Sodium bicarbonate is baking soda. It can make non-carbonated acidic drinks like juice bear some resemblance to soda with the carbon dioxide bubbles and can remove all of its acidity but probably also makes it taste too salty. Sagittarian Milky Way (talk) 02:55, 6 July 2018 (UTC)[reply]

In addition to the points above, sodium bicarbonate (actual sodium bicarbonate, not soda water) is often used an an antacid. Our article you linked to specifically mentions it although as it also mentions, alternatives are frequently preferred for various reasons. While our article primarily mentions drug like formulations which for many given simplicity, dosage etc are preferred; some people do just take regular baking soda [2], generally mixed with water. Nil Einne (talk) 03:06, 6 July 2018 (UTC)[reply]

July 7

Does hypoalbuminemia causes decrease in oncotic pressure or osmotic pressure?

Does hypoalbuminemia causes decrease in oncotic pressure or osmotic pressure? I have red two different sources which everyone says something different, one says it decreases oncotic pressure and one says it decreases osmotic pressure. Who's more correct? --2A02:ED0:6D6D:F300:E469:6A54:1B75:3955 (talk) 01:26, 7 July 2018 (UTC)[reply]

If you re-read the article Kwashiorkor that you linked in your next post, you'll see that it says in parts:

"Proteins, mainly albumin, are responsible for creating the colloid osmotic pressure (COP) observed in the blood and tissue fluids. The difference in the COP of the blood and tissue is called the oncotic pressure."

and:

"The typical swollen abdomen is due to two causes: ascites because of hypoalbuminemia (low oncotic pressure), and enlarged fatty liver."

So, to answer your first query; hypoalbuminemia doesn't cause a decrease in oncotic pressure, it is a low (decreased) oncotic pressure. To address your second query; both are correct – the oncotic pressure is the difference between the two osmotic pressures, so if you alter one of those osmotic pressures, you will by definition alter the oncotic pressure. Hope this helps. {The poster formerly known as 87.81.230.195} 90.220.213.151 (talk) 06:54, 7 July 2018 (UTC)[reply]

No, that's a badly written article, because hypoalbuminemia and low oncotic pressure are not quite the same thing. Hypoalbuminemia results in/is one cause of low oncotic pressure. Low oncotic pressure is a manifestation of hypoalbuminemia. Or put another way, decreased serum protein results in decreased oncotic pressure. Oncotic pressure is a gradient between two different environments; low albumin on one side of the gradient will increase the size of that gradient. And since albumin is synthesized in the liver, an enlarged fatty liver may be the cause of the hypoalbuminemia. As to the second question, oncotic pressure is one kind of osmotic pressure. So referring to it either way is fine, though oncotic is more specific and more ususal. - Nunh-huh 14:39, 7 July 2018 (UTC)[reply]

Why in starvation there is mainly ascites rather than edema?

After reading the article Kwashiorkor I have noticed that in photos of people (especially children) in starvation always have bloated abdomen as if they are fatty but according to the mentioned articale (as well as more articles) this is due to hypoalbuminemia. Now my question is if hypoalbuminemia causes to leak of fluid into the abdominal cavity (ascites) due to changes in osmotic / oncotic pressure, then it should be anywhere in body (edema) rather than ascites only. Isn't it? But always in photos of starvation we see only bloated abdomen so it says that there is something special in the blood vessels in the abdomen (which causes to this phenomenon in the abdomen only) that in other vessels there is no, and I don't understand what it is. 2A02:ED0:6D6D:F300:E469:6A54:1B75:3955 (talk) 01:38, 7 July 2018 (UTC)[reply]

From kwashiorkor: The typical swollen abdomen is due to two causes: ascites because of hypoalbuminemia (low oncotic pressure), and enlarged fatty liver. I suspect the fatty liver may exacerbate the ascites by causing portal hypertension. Note in the image in kwashiorkor the child also has pronounced edema of the feet. --47.146.63.87 (talk) 07:06, 7 July 2018 (UTC)[reply]

Also, re: the section title, kwashiorkor is only one type of starvation: lack of protein, but sufficient energy intake. Marasmus is the more common situation of altogether inadequate nutrition, and produces the emaciation commonly associated with hunger. --47.146.63.87 (talk) 07:11, 7 July 2018 (UTC)[reply]

[Edit Conflict] The edema in Kwashiorkor does not occur only in the abdomen, it also occurs markedly in the ankles and feet, as the article clearly states and illustrates, and may be less prominently present elsewhere. The edema article makes it clear that different parts of the body exhibit edema more, or less, according to the underlying cause: if you want to delve into the reasons for this you probably should be consulting specialist medical texts rather than a general encyclopaedia.

You say "always in photos of starvation we see only bloated abdomen", but such photos are usually taken by photojournalists for journalistic purposes, not by trained medics attempting to provide diagnostic data, and will naturally emphasise those signs which lay readers will most notice. {The poster formerly known as 87.81l230.195} 90.220.213.151 (talk) 07:15, 7 July 2018 (UTC)[reply]

Hæmatophyte (plant blood parasites)

I found this page through Wiktionary's list of dictionary-only words. It contains citations about unicellular plants (described in one entry as either fungi or algae) that infect, or live in, the bloodstream. What is this actually referring to? Are there actually algae and fungi living in the bloodstream, or do the citations refer to something else that was incorrectly classified as such? 169.228.156.220 (talk) 04:10, 7 July 2018 (UTC)[reply]

The first sentence of the last paragraph of the lead in Bacteria suggests that bacteria were formerly thought to be unicellular plants of the class Schizomycetes. The second quotation on that Wiktionary page, saying that hæmatophytes all belong "to the fungus- (or alga-) group of schizomycetes" would seem to indicate that bacteria in the bloodstream are what was meant. Deor (talk) 14:12, 7 July 2018 (UTC)[reply]

The dictionary cited was published in 1920, at a time when life was organized broadly into just "plants" and "animals". Even bacteria were so divided. Entire bacteria phyla were mistakenly assumed to be more closely related to macroscopic plants and animals based on whether those bacteria were themselves more "plant-like" or "animal-like" in behavior, diet and/or appearance. You can read more at Kingdom_(biology)#Historical_development. Someguy1221 (talk) 14:22, 7 July 2018 (UTC)[reply]

A claim in an alternative medicine book

Hulda Regehr Clark wrote a book and I'm wondering about the claims in it, and I took pictures of 3 pages, can somebody tell me what's true/false in there. For context, she claims a "zapper" can use the frequencies listed to kill the organisms in the body - https://imgur.com/a/UedEOC9 — Preceding unsigned comment added by 2001:8000:1A4F:C500:6D01:67CD:2E19:D18D (talk) 08:21, 7 July 2018 (UTC)[reply]

Quackery. DroneB (talk) 10:32, 7 July 2018 (UTC)[reply]

Yeah, I'm hoping for a scientific explanation and rejection, as I'm trying to convince somebody it's false. — Preceding unsigned comment added by 2001:8000:1A4F:C500:3157:2F30:FB6D:D91D (talk) 10:58, 7 July 2018 (UTC)[reply]

I haven't the foggiest what kind of silliness they are doing but my guess is they are measuring the resonant frequency of slides with whatever has been stuck onto it. Which would mainly depend on the slide and how much gunk was stuck on the slide. If they're thinking that has anything to do with what's on the slide or that this frequency is specific to an organism or kills it, they're in the area of pyramids and crystals and orgone energy and suchlike stuff. Dmcq (talk) 14:10, 7 July 2018 (UTC)[reply]

If people aren't convinced by understanding the importance of the null hypothesis then they cannot be convinced by anything. "Reasoning will never make a man correct an ill opinion, which by reasoning he never acquired..."--Jayron 32 14:22, 7 July 2018 (UTC)[reply]

I'm going to begin by noting that the point that Jayron raises about null hypotheses cannot be over-emphasized. Anyone who believes the word soup psuedo-science babble that is found on those three pages you shared without understanding why it's not in the same universe as anything resembling empirical rigor is so lacking in basic analytical training that you are likely to be facing a steep uphill climb in combating a probable corresponding confirmation bias. I'll give what general information I can on the underlying biophysics here though.

First, the author generally treats "frequency" as a force, like a life-energy, which can be depleted over time. This is patent nonsense. Frequency never refers to a physical force but rather a rate of occurrence across a period of time. For your friend, you might try pointing out the etymology of the word here and connect it with common vernacular uses; the frequency of their doctor's visits, from example. In the case of biology, the frequency we are talking about will generally refer to a wave, which brings us to patent nonsense point number two; the idea that there is one single "frequency" which defines all biological life. In reality, there are hundreds of different types of application of the word which may refer to different aspects of an organism's physiology. Any form of radiation which is generated by our interacts with tissue has its own frequency. As Dmcq pointed out, various forms of biomass will demonstrate different wave patterns under spectrometry. Brainwaves have a frequency, as do action potentials (actually they have two, the frequency of their firing and the wave which propagates across the axon). Even the beating of the heart can be expressed as a frequency. The idea of one single master frequency that is more important than any other or which comprises all others is nonsensical. If you said "there is a positive correlation between long life and the quantum inhibitability of cross-flux semi-habitual nano-factor impressions" it would make exactly the same amount of sense (which is to say, none)--one is merely more easily recognizable as pseudoscientific nonsense.

Additionally, there is no correlation between age or good health and a general increase or decrease of all frequencies in an organism. Most frequencies relevant to a biological process will vary over time, and some will either increase or decrease with ill health or death. And even if an organism dies, not all wavelengths will flatline; some of the matter that made up the body will continue to exhibit the operation of wavelengths relative to its physical properties. Lastly, the author doesn't even seem to have a self-consistent notion of what they mean by "frequency"; sometimes they treat it a measurement (which is at least accurate in the general sense) and other times they use it as quanta, which makes no sense in any context. In the first few sentences of the passage, they use it for both in the same extended thought!

Honestly, I could go on for days; so far we've only tapped into the misuse of nomenclature, but there's also the volume's-worth of commentary you could make on their methodology (or lack thereof) for this "scientific inquiry". In short, not only is this not good science, but I have doubts as to whether the author could pass a secondary school course in biology with a very patient instructor. Snow ^{let's rap} 12:27, 8 July 2018 (UTC)[reply]

Thanks! I'll show them what you wrote. — Preceding unsigned comment added by 2001:8000:1a4f:c500:3177:c7b9:7c56:7efe (talk) 08:04, 11 July 2018 (UTC)[reply]

Well done. I clicked the link but honestly couldn't make my way past the first paragraph. "Not even wrong" doesn't do it justice. Matt Deres (talk) 15:17, 8 July 2018 (UTC)[reply]

I think this is a rare hybrid of "very wrong" and "not even wrong". --Stephan Schulz (talk) 17:22, 8 July 2018 (UTC)[reply]

Did the eating of crabs and anchovies originate in South America?

Article List of food origins lists anchovies and crabs as food that originated in South America. I'm a bit skeptical. I'm not questioning the fact that people in South America may have eaten anchovies and crabs for millenia but I'd tend to believe people in other parts of the world did not have to wait for the discovery of America to start eating them. What's the story? People do tend to insert nonsense in that article (I've had to remove "rice" as food originating in Central America!) but here I'm not entirely sure. Basemetal 14:44, 7 July 2018 (UTC)[reply]

Anchovies have been eaten in Europe since ancient times. Looie496 (talk) 16:11, 7 July 2018 (UTC)[reply]

An IP made a bunch of edits last October, including this one.[3] ←Baseball Bugs ^{What's up, Doc?} carrots→ 18:54, 7 July 2018 (UTC)[reply]

Most, if not all of it, seems to be BS. That page has got 42 watchers. Great job guys. Basemetal 18:59, 7 July 2018 (UTC)[reply]

Would it make sense to revert back to just before the IP went wild, and then add back anything that might be factual? ←Baseball Bugs ^{What's up, Doc?} carrots→ 19:07, 7 July 2018 (UTC)[reply]

I think that's a bit drastic. Besides I know nothing about this topic. Do you? Maybe the best thing is to see what that guy's edits were and to take out what seems presposterous (after checking WP articles that they are indeed so). His was IP 167.57.164.2 and his edits were all made between 01:30 and 04:25 on October 11 2017. Btw, not all of his edits seem to be wrong. But, from a quick look, the ones in the "Sea food" section seem to be, most of them. Basemetal 19:46, 7 July 2018 (UTC)[reply]

I'm getting a hunch as to why the 42 watchers didn't do anything about it. Too much work. ←Baseball Bugs ^{What's up, Doc?} carrots→ 20:43, 7 July 2018 (UTC)[reply]

This discussion belongs on the article's Talk page. Akld guy (talk) 21:11, 7 July 2018 (UTC)[reply]

Thus ensuring it will remain as it is. ←Baseball Bugs ^{What's up, Doc?} carrots→ 21:53, 7 July 2018 (UTC)[reply]

" the discovery of America "

Please tell me you're not dating that to 1492... Andy Dingley (talk) 23:37, 7 July 2018 (UTC)[reply]

Within the context of the question, what else makes sense? Matt Deres (talk) 15:24, 8 July 2018 (UTC)[reply]

Per Stan Freberg, et al, it could also be said that in 1492 America discovered Columbus. ←Baseball Bugs ^{What's up, Doc?} carrots→ 16:02, 8 July 2018 (UTC)[reply]

Just to add to the story, there is extensive evidence of Aboriginal Australians having eaten crabs for tens of thousands of years. One source (out of many available) is https://australianmuseum.net.au/food-from-the-sea-shellfish-crustaceans. Will have a look at List of food origins to see how I can help there. HiLo48 (talk) 00:43, 8 July 2018 (UTC)[reply]

Just skimming that article now. I note that it lists Eucalyptus as a food of Australian origin. Sure, eucalyptus trees are from Australia, but the only mammals I'm aware of which can digest the leaves are the Koala and the Wombat. The caterpillars of some insects eat them. Maybe ants too. I suspect humans would become very ill from eating them. Termites eat the wood, of course. I wonder which of those the writer had in mind when listing it as a food? HiLo48 (talk) 00:59, 8 July 2018 (UTC)[reply]

Not exactly a food, but eucalyptus tea has been used medicinally for thousands of years. Looie496 (talk) 16:27, 8 July 2018 (UTC)[reply]

Really? I've never heard of it. (But there's a lot of things I've never heard of.) I see now on the web that it exists, but it's the "thousands of years" bit that interests me. Got a source? HiLo48 (talk) 03:03, 9 July 2018 (UTC)[reply]

No. But it is a traditional medicine for the aborigines, and for them, a thousand years is a short time. Looie496 (talk) 17:01, 9 July 2018 (UTC)[reply]

I'm just a little bit sceptical about it being a traditional medicine for aborigines. Not saying it couldn't be, but I have worked with, lived with and studied Australian Aboriginal people and their culture a reasonable amount, and haven't heard of it. Hence my asking for a source. HiLo48 (talk) 22:46, 9 July 2018 (UTC)[reply]

According to this,[4] eucalyptus tea can be consumed, while the oil should only be used externally. Maybe that's what the user means by it being used as a "medicine". ←Baseball Bugs ^{What's up, Doc?} carrots→ 23:44, 9 July 2018 (UTC)[reply]

Eucalyptus oil is certainly very popular in the traditional medicine of Indonesia where it is known as id:minyak kayu putih for the treatment of various ailments, but particularly id:masuk angin. 202.155.85.18 (talk) 01:38, 10 July 2018 (UTC)[reply]

I know about eucalyptus oil being used as an external medicine. That certainly is a traditional use among Australian Aboriginal people. But I still have my doubts about the tea. That sounds to me more like a modern, yuppie fashion. HiLo48 (talk) 08:16, 10 July 2018 (UTC)[reply]

That was added about 9 1/2 years ago, by a user who has been inactive since 2011.[5] ←Baseball Bugs ^{What's up, Doc?} carrots→ 01:29, 8 July 2018 (UTC)[reply]

I'd note the lead of the article mentions that a lot of types of seafood and crabs is one it singles out, were often eaten on every continent. Nil Einne (talk) 07:59, 8 July 2018 (UTC)[reply]

The Romans loved a fermented fish sauce called Garum, which was most commonly made out of anchovies. They used it as a condiment like soy sauce. Cullen³²⁸ Let's discuss it 03:23, 9 July 2018 (UTC)[reply]

July 8

Full face diving mask Vs mouth piece

Thinking about the Thai cave rescue I wondered which would use air quickest a full face mask or a mouthpiece. On one hand a full face mask would need air flow through all the time. On the other hand a mouthpiece means that air breathed out is used up even if there could be enough oxygen to breathe it again mixed with some fresh air. Intuitively I think you should be able to tune the flow of a full face mask to use air more slowly, though that might seem stale to the diver. -- Q Chris (talk) 16:27, 8 July 2018 (UTC)[reply]

Pure speculation but they may be using rebreathers since they have to stay underwater for a long time and supplying cylinders is difficult. This would mean they use up a large percentage of the oxygen in the cylinders. I found breathing in through my mouth rather than my nose difficult. Dmcq (talk) 17:07, 8 July 2018 (UTC)[reply]

(ec) Take a look at full face diving mask. Both mouthpieces and full face masks usually have on-demand air supply, i.e. you "suck" the air through a valve (more precisely, the equaliser valve opens when it detects underpressure). Both will normally also release the overpressure when you breathe out. You cannot create an over- or underpressure that would allow you to "store" air that you breathe out in the mask - neither would your lungs stand it, nor would the seal of the mask hold it. Low oxygen content is not a problem, as the partial pressure even of quite oxygen-depleted air under pressure is high. This allows experienced divers to reduce their rate of breathing to below normal - they still get plenty of oxygen, but you need to train the body to notice that. If you want maximum endurance, you can use a rebreather. These are available for full-face masks and for more normal mouth pieces. --Stephan Schulz (talk) 17:17, 8 July 2018 (UTC)[reply]

I suspect the issue might be that a conventional mouthpiece has to be held between the teeth - not fail-safe for an untrained kid liable to panic. "Wearing full-face masks, which are easier for novice divers than traditional respirators..." BBC News - Thailand cave rescue: Mission to save boys under wayAlansplodge (talk) 19:28, 8 July 2018 (UTC)[reply]

Officials Call for Donations of Small Diving Masks to Rescue Cave Boys

Full face diving mask

Amazon: Divers Full Face Mask

--Guy Macon (talk) 22:27, 8 July 2018 (UTC)[reply]

For what it's worth, PADI (one of the world's largest recreational SCUBA diving organizations) treats a full face mask as a specialized skill that requires extra training beyond the basic open-water SCUBA certificate. Rebreather Diver is a formal certificate, and before PADI will grant it, the diver must satisfy experience minima and obtain the enriched air training and certificate, also known as breathing NITROX. Other dive agencies have similar requirements.

Breathing an atmosphere other-than-air can feel very strange; it requires skill and discipline to avoid physiological harm; in the case of an emergency rescue, the rescue divers would have to weigh any benefits against these serious extra workloads and risks.

Of course, diving in a cavern (or any other confined space) is an extremely advanced skill; and it can be extremely dangerous even in recreational settings. This rescue operation certainly falls under extraordinary circumstances; no dive instructor would want to put novice divers into such conditions if it could be avoided. As in any emergency, standard rules and procedures take a backseat to making a safe and rapid egress.

Nimur (talk) 01:54, 9 July 2018 (UTC)[reply]

I did notice that the PADI training has a lot about setting up the mask properly (which someone experienced would do in this case), that there would be opportunity to take the children down in short test dives to see if they have any problems, and that they wouldn't have to swim but rather be dragged along. They might even administer a sedative. And of course there is no alternative. Clearly it worked with four kids so far. I wonder if they started with the sickest or with the most healthy (to work out any bugs in the system)? --Guy Macon (talk) 05:59, 9 July 2018 (UTC)[reply]

Media reports suggest the initial plan was possibly to bring out the strongest, but after an assessment by a doctor the decision was made to bring the weakest out first [6] [7] [8]. According to those reports, this may have been in part, other than greater urgency for them to leave, also because it was expected that the conditions could be the best they would ever have. Nil Einne (talk) 08:50, 9 July 2018 (UTC)[reply]

July 9

Puncture repair patches - what's the orange stuff?

Puncture repair patches typically have a black part and an orange part but I've also seen patches that are just a big piece of buytl rubber which you can cut pieces off and they don't have the orange stuff. So what is the orange stuff? --129.215.47.59 (talk) 14:12, 9 July 2018 (UTC)[reply]

The orange layer is cold-vulcanizing uncured rubber.[9] When you put it on a clean neoprene surface with cold-vulcanizing fluid (commonly -- and incorrectly - called "adhesive") it melts into the surface The black layer is neoprene, which is stronger than cold-vulcanized rubber and more resistant to blowouts. --Guy Macon (talk) 15:29, 9 July 2018 (UTC)[reply]

The black part is butyl rubber (not neoprene) and is filled with carbon. That makes it strong and stiffer, but also less elastic. If you join two pieces of this together with a glue, then it's an inelastic joint which stresses the glue layer and causes an early failure. The softer unvulcanised rubber acts as a mechanical interface and shoc absorber between the two. As it's then a sandwich between them, it doesn't need to be especially strong.

Butyl to butyl joints are fine when made carefully in the workshop (and they're glued right to the edges) - but for a quick repair on the road, the orange layers will do a better job. Andy Dingley (talk) 16:35, 9 July 2018 (UTC)[reply]

Thanks for the correction. --Guy Macon (talk) 14:50, 10 July 2018 (UTC)[reply]

July 10

Surviving a firenado

Could a person survive getting sucked into a “firenado”? The question was inspired when I watch Into the Storm where a man got sucked into a firenado and die. Planet Star 00:40, 10 July 2018 (UTC)[reply]

Responders who want to tackle this one might want to peruse Into the Storm (2014 film) and Fire whirl. People occasionally survive all manner of seemingly unsurvivable events, but I'd think that being drawn into a tornado of essentially turbocharged gasses burning at 1,000°C would be quite hard to survive, as even if the victim was thrown clear quite quickly, a breath or two would likely cause fatal lung damage. I haven't myself been able to find any authoritative references specific to 'firenadoes', however. {The poster formerly known as 87.81.230.195} 90.212.98.167 (talk) 02:11, 10 July 2018 (UTC)[reply]

Why are the Great Plains of North America not considered to be a system of piedmont plateaus?

Or thought of as one.... A plateau is a high plain. Piedmont plateaus are plateaus that are bordered on one side by mountains and on the other by a body of water or a plain as is the case with the Piedmont Plateau east of the Appalachian mountains and west of the Atlantic Plain, and the Appalachian Plateau on the west of these mountains and east of the Central Plains. That all sounds like the Great Plains. The high plains of the Great Plains are west of the lower Central Plains and east of the Rocky Mountains. The Great Plains reach heights higher than 6000 ft above sea level in some areas. For example, Colorado Springs is around 6035 ft above sea level and Cheyenne, Wyoming is around 6062 ft in elevation. The Continental Divide is around 11000 ft in elevation, but the peaks of the Rocky Mountains can reach above 13000 to 14000 ft in elevation. One can see the the land rising as one approaches the Great Plains in some areas. What characteristics do the Great Plains lack from a piedmont plateau or is it actually a system of piedmont plateaus? Willminator (talk) 03:35, 10 July 2018 (UTC)[reply]

Have you read Great Plains? ←Baseball Bugs ^{What's up, Doc?} carrots→ 04:54, 10 July 2018 (UTC)[reply]

It may be true that you can see the land rising as you approach them in some places but the part I crossed was very flat. It's a mile high drop but hundreds of miles wide and some elevation ranges of that mile are surely steeper than others. The Plains are ~~mostly volcanic ash deposits from the Rocky Mountains erupting since before the range was the height of the Himalayas or Andes, the further east the less ash and the closer to sea level.~~ Sagittarian Milky Way (talk) 05:30, 10 July 2018 (UTC)[reply]

"Mostly volcanic ash..."? That isn't how I learned my geology. The U.S. Geological Survey summary of the interior plains describes a great inland sea from which sediments accumulated and compressed.

Nimur (talk) 11:35, 10 July 2018 (UTC)[reply]

Huh, you are correct. How far west did the sea ever get? Sagittarian Milky Way (talk) 12:57, 10 July 2018 (UTC)[reply]

Well, that's a complicated question because over geological time-scales, the continents have moved and changed shape. For a start, here's the Wikipedia entry on the geologic timeline of Western North America and the main article on the geology of North America. If we go far back into ancient paleo-history, the areas that are now the great plains were underneath the western ocean abutting the continent of Laurentia; the far west parts of our continent (like California's Sierra Nevada mountains) didn't exist yet because the Nevadan orogeny didn't occur until the late Jurassic era... but this is all a vast simplification. Like all questions of science - how many years do we want to spend on the topic to refine and perfect our understanding?

When I used to teach geology for small kids, we gave a brief summary suitable for early elementary school: you can find fossils of seashells in the mountains of Colorado and Utah because a lot of that land used to be the bottom of the ocean. Once again, we're so severely oversimplifying that we run the risk of lie to children-style factual error.

A great book, for the interested reader: The Geology of North America: An Overview (1989); available at Amazon. One reviewer wrote, "...very dense and pretty dry..." Well, what can one expect from a book on rocks?!

If we want to get very precise about the exact farthest west extent, and so on, all I can say is that I am reminded of our discussion in March, quibbling on the details about the exact age of Earth. How shall we measure west-ness in paleo-Earth? Should we measure degrees of longitude, from the Greenwich meridian to the easternmost tidal high water mark? ... and where exactly was Greenwich, so many million years ago? These are, ultimately, issues that relate to false precision. Paleo-geology is a different kind of science than analytical chemistry; geologists have to accept an amount of intrinsic uncertainty; and so we accept that we must maintain the scientific method without any ability to conduct controlled experiment. But at the same time, we can hold ourselves to the highest standards of analytical investigative rigor.

Nimur (talk) 14:53, 10 July 2018 (UTC)[reply]

So in the case of the Great Plains, it matters how steep and long the slopes are from a plain or sea to the top of a piedmont plateau in order for it to be classified as a piedmont plateau and not just a high plain? Willminator (talk) 14:42, 10 July 2018 (UTC)[reply]

The U.S. Geological Survey's scheme for classification is centered around the idea of a "geological province," which is a concept they invented to group areas that have similar geological histories (and therefore, similar geological properties). But they use terminology fluidly: a region has specific areas that "exhibit the geology of the interior plains," even if there are counter-examples.

The term "piedmont" is used to refer to a specific, different area of the United States. In that sense, which is the canonical usage defined by the USGS, the word "Piedmont" is used as a locale, not as a generic description. For more information on this standardization of terminology, Wikipedia has an article on United States physiographic regions.

Nimur (talk) 14:53, 10 July 2018 (UTC)[reply]

I think the key thing that makes a plateau a plateau is that you can look up at it. According to the article, it is "raised significantly above the surrounding area". In the case of the Piedmont Plateau, there is an edge called the Atlantic Seaboard fall line. Though it's an obscure feature now, apparently at one point it meant a bunch of sweaty guys had to lug a canoe a long distance uphill practically any way they tried to boat inland, so it counted as a highly noticeable feature to them. The Great Plains don't have this AFAIK. Wnt (talk) 16:12, 10 July 2018 (UTC)[reply]

The Atlantic Fall Line can be quite dramatic in places and there's a clear delineation, for example, between the Atlantic Coastal Plain and the Piedmont all up and down the East Coast, from the Metacomet Ridge in Connecticut to the The Palisades in New Jersey. If you've ever crossed the George Washington Bridge, you're basically staring at the escarpment that marks the Eastern edge of the Piedmont. I live in Raleigh, NC which lies right on the fall line, and it's obvious when you're approaching it: South and East of Raleigh is flat: there's very little hills or elevation changes. In Raleigh, there are some fairly dramatic elevation changes in the area of the North Hills and the Crabtree Valley which clearly mark the transition to the Piedmont. There's also an even more dramatic transition from the Piedmont to the Appalachians, the Blue Ridge Escarpment, which you notice dramatically on any highway going west through the Carolinas or Virginia. By contrast, when traveling West across the Great Plains, there's no dramatic escarpments or changes in elevation. It's true that the great plains can get quite high as elevation gradually ramps up from East to West, but there's no clear boundary the way there is for the Piedmont.--Jayron 32 23:47, 10 July 2018 (UTC)[reply]

Here's the Palisades. There's still ridges of ancient metamorphic rock east of them, only about half the height of the Palisades at the GWB though. Beyond West Bronx and the skyscraper district with the tallest non-Manhattan building there's still naked eye hills over 200 feet above sea level but they're just piles of glacial detritus like terminal moraines. Sagittarian Milky Way (talk) 02:57, 11 July 2018 (UTC)[reply]

High index lenses

Are there any disadvantages to a 1.74 high index lens compared to one of lower index such as 1.67? I.e. Why doesn’t everyone with strong prescriptions get 1.74 instead of 1.67? Clover345 (talk) 07:52, 10 July 2018 (UTC)[reply]

Cost. Tigraan^{Click here to contact me} 09:54, 10 July 2018 (UTC)[reply]

Agreed. I have terribly myopic eyesight and shell out the extra for the high index lenses. When it comes time to pick out lenses, my optician and I typically have to sift through several pages of various strengths and coatings to get some reasonable trade-off between price and utility (fashion falling a distant third). People requiring the higher index lenses also typically require other modifications as well, driving up the price again. For example, my optician makes several modifications to the grinding of the edges to reduce glare simply because there's more lens there to cause it. Matt Deres (talk) 12:20, 10 July 2018 (UTC)[reply]

I have one of each. My eyes are strongly asymmetrical and although my prescription for one eye is strong enough to justify high index lenses anyway, I get a more mechanically balanced pair of lenses if the thicker lens is made thinner, but not the thinner one, so they end up matching more closely. It also has an effect on opacity for sunglasses.

Of course, graded index lenses would be even more interesting. Andy Dingley (talk) 13:28, 10 July 2018 (UTC)[reply]

While cost is a big factor, it isn't the only disadvantage. Coatings was mentioned above, but not clearly mentioned is one reason for coatings is because of the lenses. Higher index lenses generally mean more reflections, hence why nearly all high index lenses come with AR coatings. (And that can lead to other things like scratch resistance.) This is mentioned in the above linked source about cost but is also discussed here [10]. As mentioned there you also tend to get more chromatic aberrations, or other distortions of peripheral vision with high index lenses. (Also mentioned here [11] [12].) Although as mentioned, this tends to be a bigger problem for those with low powered prescriptions because those with higher powered ones are often more used to limitations of their peripheral vision. As sort of hinted there and also mentioned above, it also depends on the skills of the optometrist or whoever is designing the glasses/dispensing the prescription, along with choosing the best option, working with the patient. See e.g. [13] [14]. As mentioned in a the second source, a notable advance is using computerised tools to give a more precise individualised solution generally called digital, HD or free-form lenses [15] [16]. Nil Einne (talk) 15:47, 10 July 2018 (UTC)[reply]

How do Voltage converters deal with Hz?

Do voltage converters from 220/240 to 110/120 or from 110/120 to 220/240, normally also convert the between 50 and 60 Hz? I know most devices won't need a converter anymore and that this might be indifferent for most appliances, but sometimes it matters. --Doroletho (talk) 18:34, 10 July 2018 (UTC)[reply]

No. It's rarely necessary to do this. When it is, it's usually easier to replace the 60Hz motor with a 50Hz one (it's almost never necessary to do it the other way). For US machine tools imported to Europe, it's sometimes necessary to do this because poorly designed motors overheat on 50Hz as their design was marginal in the first place. Andy Dingley (talk) 20:30, 10 July 2018 (UTC)[reply]

And besides motors, are other devices affected by the 'wrong' Hz? Some devices set their internal clock through the electric power. Wouldn't these be heavily affected, specially if they run on a timer and require exact running times? --Doroletho (talk) 21:12, 10 July 2018 (UTC)[reply]

A timer or synchronous clock doesn't just require conversion, it needs accurate conversion. Such a thing is possible, but I've never seen anyone bother to do it. We do already have clocks in Europe - it's cheaper to just use a local one. Andy Dingley (talk) 21:19, 10 July 2018 (UTC)[reply]

Some clocks do use grid frequency to synchronize (at least in Europe). Of course, a 50/60Hz mismatch would make the clock completely useless, not "slightly missing on the precise time". Tigraan^{Click here to contact me} 08:57, 11 July 2018 (UTC)[reply]

Another device that the frequency affects is a transformer, though 50 and 60 Hz are close enough that I don't think it's likely to matter. See Transformer#Effect of frequency. --76.69.47.228 (talk) 09:40, 11 July 2018 (UTC)[reply]

Most converters don't change the frequency. It is possible to get "inverters" or "frequency converters" that do this, though even the cheap ones are generally hundreds of dollars. Most electronics don't care about the frequency very much, and of those that do (e.g. things with motors or cheap timing circuits), it is often easier/cheaper to buy a version that is designed for the local frequency than it is to import a foreign version and buy an inverter. Dragons flight (talk) 08:20, 11 July 2018 (UTC)[reply]

July 11

copper pitchers for storing drinking water

The alleged beneficent results of drinking water stored in copper pitchers have caused great demand for them and they are selling hot on Amazon India and other online stores. Numerous sites display pages describing such benefits. Are there chances of copper poisoning from drinking water stored in a copper pitcher? — Preceding unsigned comment added by 2405:204:D00C:7689:5D99:8D01:C88E:2E5D (talk) 16:28, 11 July 2018 (UTC)[reply]

This study says that storing drinking water in copper vessels has clear benefits in killing off bacteria in the water and that "Safety of leached copper does not appear to be an issue since studies have shown that the current WHO guideline of 2 mg Cu/L is safe ...., and the levels leached in the study were 1/20th of the permissible limits." Mikenorton (talk) 16:38, 11 July 2018 (UTC)[reply]

It's noted in hospitals the spread of infection has greatly increased after copper worktops (which killed bacteria) were replaced by plastic ones. 46.208.78.215 (talk) 18:41, 11 July 2018 (UTC)[reply]

Who says so? ←Baseball Bugs ^{What's up, Doc?} carrots→ 18:45, 11 July 2018 (UTC)[reply]

I don't know about any historic changes but Antimicrobial copper-alloy touch surfaces mentions clinical trials on new products. BTW we also have articles on Antimicrobial properties of copper and Copper alloys in aquaculture. Nil Einne (talk) 19:03, 11 July 2018 (UTC)[reply]

Copper is a poor choice, as it has toxicity risks. Although it also has antibacterial benefits, these are shared equally well (possibly better) by brass or monel fittings, which avoid the risks.

Copper is a risk depending on the water inside it. Hard water is fine, but something more acidic is a risk. Some contents - such as vinegar, pickles etc. involving acetic or lactic acid are downright dangerous. Andy Dingley (talk) 19:36, 11 July 2018 (UTC)[reply]

The above two articles for touch surfaces (which focuses a lot on in healthcare settings) and aquaculture at first glance seem to mostly deal with alloys given the titles.

However if you check the touch surfaces one, sometimes it simply refers to copper. Most of the time it's unclear if this specifically means near pure copper or just a simplification of copper containing alloys. However they do mention C11000 foil which seems to be basically a form of pure copper (see Oxygen-free copper, [17] [18] although note as mentioned in those sources silver is counted as copper) is used for cladding bed rails in one hospital. The EPA also has a group which seems to cover pure copper group I 95.2% to 99.99% 82012-1 although of course it doesn't necessarily mean these products are used in hospitals. Note that from reading all these sources, it seems one complication is probably that from what I've seen in the earlier articles, is what you count as an alloy e.g. C11000 may be called a copper-alloy although from what I understand as said earlier it's basically pure copper. (While you don't have to have much of something else to reasonably be called an alloy e.g. steel, from the earlier sources it seems like C11000 often does not intentionally include anything else. In other words, other components are impurities rather than add to make an alloy.)

Anyway point being, while the reasons for the various choices isn't really mentioned at least with some healthcare surfaces I'm not sure whether it's true that copper alloys are always definitely better than what may reasonable be called copper. (And I'm also not convinced that the reason for choosing an alloy rather than simple copper is because of toxicity concerns.)

BTW that earlier article for touch surfaces mentions brass. However it does not mention monel and at least for EPA approved surfaces, it seems monel isn't suitable or at least hasn't yet been demonstrated as it says all of the registered ones have over 60% copper. They do have other Cupronickel alloys with a significantly higher percentage of copper e.g. C70600 [19] is one mentioned for the same hospital mentioned earlier.

Nil Einne (talk) 04:28, 12 July 2018 (UTC)[reply]

Here in Australia there has been some recent media hype about old "copper" plumbing fittings actually containing some lead, and hence being a potential source of lead poisoning. Being slightly technical, this is an area where I don't trust journalists in the mass media at the best of times. Most have no scientific training. But it struck me as possible. HiLo48 (talk) 23:44, 11 July 2018 (UTC)[reply]

The lead is more likely to come from the solder used to join the pipes. Make sure the water container is not soldered with lead containing solder. Graeme Bartlett (talk) 00:50, 12 July 2018 (UTC)[reply]

For greater clarity: read "lead-containing solder" or "solder containing lead". --76.69.47.228 (talk) 10:03, 12 July 2018 (UTC)[reply]

Ah yes, old solder. That makes sense. HiLo48 (talk) 07:54, 12 July 2018 (UTC)[reply]

European practice for some years now is that soldered joints for potable water need to be made with lead-free solder.

There's still plenty of short stubs of lead pipe around in old houses, usually the main water supply into the house. In most water conditions, this isn't a problem (the pipe interior is coated with a layer of deposited minerals). In places where the water will corrode the lead, more of such pipes have been replaced by now. To connect modern piping to old lead it's necessary to use a mechanical pipe fitting, not a soldered joint. The specific type of soldered joint used to connect to old lead requires a leaded solder, so can no longer be used on potable water (by the regulations), even though it's still permissible to leave the old lead pipe in use. Andy Dingley (talk) 10:03, 12 July 2018 (UTC)[reply]

Regulations will vary widely around the world. The OP is presumably in India. HiLo48 (talk) 10:06, 12 July 2018 (UTC)[reply]

Metallic copper probably has little or no toxicity. It's the copper salts, such as copper sulfate, that are toxic. But you'd need to ingest about 10 to 20 grams copper sulfate in order to die. Copper sulfate ingestion is relatively popular for committing suicide in India. Acidic foods such as vinegar, pickles etc. are already preserved by the acid, so there's no further benefit from putting them into copper vessels. --46.189.28.77 (talk)

Doctors that refuse abortions

is there a name for a doctor who refuses to perform an abortion (in a country where abortion is legal), based on personal beliefs? The source I have checked calls it a "Conscientious objector", but I'm not sure if we should use that term in Wikipedia's voice, as it seems to be specific to the military. The source probably uses it simply because it conveys a similar idea.

NOTE: I'm not asking for help or medical advise about abortions, just a name. I'm writing an article about a proposed abortion law, and I want to make sure that I'm using the right terms. Cambalachero (talk) 19:07, 11 July 2018 (UTC)[reply]

Maybe see Hippocratic Oath. ←Baseball Bugs ^{What's up, Doc?} carrots→ 19:37, 11 July 2018 (UTC)[reply]

"Conscientious objection" does appear to be the commonly used term. Searching google for "Conscientious objection abortion" finds many relevant hits.-gadfium 20:07, 11 July 2018 (UTC)[reply]

"Conscientious objection" is the term used in the Abortion Act 1967, Section 4. See also [20], [21]. --46.189.28.77 (talk) 20:14, 11 July 2018 (UTC)[reply]

And it's the term used by newspapers like The Guardian, but others refers to them as "abortion refuseniks" like The Spektator which is a misnomer, since refuseniks were the object of a denial, and not denied something actively themselves. --Doroletho (talk) 21:21, 11 July 2018 (UTC)[reply]

Japanese home appliances in a country split between a 50 Hz and 60 Hz power grid?

Japan, as a very rare exception (Brazil is another, don't know about others), has a power grid split between a 50 Hz and a 60 Hz area. Are there home appliances versions for each area? Are home appliances designed upfront with the idea in mind that they might be used in one or the other area (and therefore made to be tolerant of deviations)?--Doroletho (talk) 21:35, 11 July 2018 (UTC)[reply]

Virtually all this list of home appliances, consumer electronics and AC adapters tolerate the difference between 50 Hz and 60 Hz mains frequency with only a minor exception of older electric clocks, tape recorders and record players that employ synchronous motors whose rotation period is an integral number of AC cycles. West Japan uses 60 Hz and east Japan uses 50 Hz; on the boundary between the regions there are back-to-back HVDC sustations that convert the frequency. DroneB (talk) 22:48, 11 July 2018 (UTC)[reply]

Note that some home appliances which are affected by mains frequency e.g. clock radios have a 50/60 Hz switch. These devices don't generally have synchronous motors of course and developing a product with one which can easily cope with both frequencies is I imagine difficult enough that it is basically very rarely if ever done. Nil Einne (talk) 04:35, 12 July 2018 (UTC)[reply]

The one device which both depended upon frequency and couldn't easily be changed was the synchronous motor. I've some industrial cam timer switches here which run on 50Hz, but they're designed for the US market too. As their motors are standardised, it's a two-screw operation to swap the motors. Motor makers for these just make them in two forms, with the same final speed. I've even got old (unusued) spares of 60Hz US motors for them, taken off US-built equipment and swapped over when it was imported. The motors run fine on 50Hz, they just run slow.

My woodworking machinery (the large fixed stuff) runs on induction motors, rather than the brushed universal motors that a smaller or cheaper power tool tends to use. These are also related to line speed, so my machines here run more slowly than they would in the US. These motors run at fixed speeds (either a nominal 1500 / 1800 rpm or 3000 / 3600 rpm, depending on their 4 pole vs. 2 pole design, and the 50Hz / 60Hz line frequency), so they often have a pulley and belt drive to change the speed to what suits the machine. If I wanted to, I could change the pulley by a small amount to bring the speed back to the original speed - but it's rarely needed. Andy Dingley (talk) 10:16, 12 July 2018 (UTC)[reply]

July 12

Glandular fever not found in a blood test, even though it's supposed to remain in the body for life

Somebody is saying that they had Infectious mononucleosis (glandular fever) and when they recovered, had a blood test and the virus was not found. But the glandular fever virus is supposed to remain in the body for life right? Is it possible a blood test wouldn't find it or some other explanation? — Preceding unsigned comment added by 2001:8000:1A4F:C500:2169:E3AB:DAE4:2459 (talk) 02:24, 12 July 2018 (UTC)[reply]

Depends on which test was done. As you can read further at Infectious_mononucleosis#Serology and its sources, most blood tests for Epstein-Barr are actually for the antibodies your body raises against the virus. Once it has been in the latent phase for a while, most of those antibodies become undetectable. There is also the possibility of a false-negative. Someguy1221 (talk) 02:57, 12 July 2018 (UTC)[reply]

In latency the virus is tightly controlled by the immune system and it is usually undetectable because it is present in the blood only in very low numbers. Ruslik_Zero 06:40, 12 July 2018 (UTC)[reply]

Spatial memory

What games (video games, traditional games, etc) are scientifically proven to enhance spatial memory? — Preceding unsigned comment added by 149.129.219.94 (talk) 07:14, 12 July 2018 (UTC)[reply]