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September 6

Objectively, when has the US been lucky with tropical cyclone damage?

Has anyone simulated enough hurricane seasons in a computer that each place gets the worst plausible storm many times and found out what the expected value of damage per year is? (either assuming the world is always like when the study was done or adjusted for less development and/or inflation in the past) What is this number? Then one could pick a date to start adding up damage totals (I'd pick end of WW2, beyond all but the old-timers' memory) and see when we've been ahead. Perhaps we were ahead right before Hugo (because of the below average early 60s-'94 Atlantic multidecadal oscillation period). Then Andrew came, then the above average 1995-future AMO period and 2004-5 and 2012 and 2017 and I wonder what year America stopped being overdue for a correction (like California is with earthquakes). Could we even still be due for a correction now? New Orleans has been hit but Miami, Tampa and Houston haven't been hit hard for a long time (if Harvey was bad then imagine a Cat 4 or Cat 5). I would be interested in the expected value of tropical cyclone damage/year without global warming (even though it would probably make a big difference in the future) Sagittarian Milky Way (talk) 01:12, 6 September 2017 (UTC)

Now That's an interesting question! There are a lot of models by climatologist that predict a long term (over 50 to 1000 years) increase, and a bunch of short-term models by meteorologists that predict what will happen tomorrow, next week, or maybe a bit longer, but I have seen nothing like what you describe. Doing that would have to predict things like El Nino, the temperature and path of the gulf stream. the path of the high altitude jet stream, etc. The climatology models can ignore all that because it averages out over those long time frames. The meteorologists can ignore all of that because they can measure the current gulf stream temperatures, etc. Also there is a lot of randomness -- the last hurricane got stuck in one place because of high pressure systems on both sides, and we cannot predict the location high or low pressure systems even a few months from now. Another oft-ignored aspect is this; gulf coast cyclones tend to hit the US and thus get a lot of study. Cyclones hitting other countries, not so much, and cyclones that stay over the ocean even less. --Guy Macon (talk) 07:02, 6 September 2017 (UTC)

You're looking for a type of ensemble forecasting. Check out Atlantic Hurricanes over the past 1500 years [1], Impact of Atlantic multidecadal oscillations on India/Sahel rainfall and Atlantic hurricanes [2], Whither Hurricane Activity [3], Normalized Hurricane Damages in the United States: 1925–95 [4]. SemanticMantis (talk) 15:07, 6 September 2017 (UTC)

• Simulations of this sort are never very convincing, because lots of weather phenomena show a distribution resembling pink noise, also known as 1/f noise. As a consequence, events that are expected to be rare, such as "100 year storms", actually occur a lot more frequently than predicted. Looie496 (talk) 00:14, 7 September 2017 (UTC)

  Estimating the rates of rare events is difficult, but your criticism is too simplistic. If you know that your weather phenomena had a simple pink noise distribution then you would use that distribution in determining the 100-year recurrence rates, and the stats would be just fine. Often the tail of a distribution is not something that can by simply extrapolated from the common events (as fitting a pink noise distribution would imply). In some cases, the underlying physical processes are simply different. For example, the frequency of certain rain amounts during common rain storms provides next to no information about the possible rainfall during a hurricane. Much of challenge is in estimating the shape of the tail of distribution. Also, when it comes to things like floods, accurately determining a 100-year flood plain means knowing not just the amount of rain but also how it will interact with the ground. Many flooding problems have occurred due to inaccurate groundwater flow models even when the rainfall risk was predicted correctly. Dragons flight (talk) 13:52, 7 September 2017 (UTC)

With all due respect, aren't you a neuroscientist? My point being, maybe extend a little good faith to the scientists who have devoted their lives to study of atmosphere, climate, and weather. I suspect they may hold some uncharitable opinions on whatever your specific area of expertise, but in science, not all opinions are equally valid. SemanticMantis (talk) 15:34, 7 September 2017 (UTC)

Well, before I went into neuroscience I was a math graduate student focusing on dynamical systems, so I'm not totally ignorant here. But I don't think I was actually criticizing climate scientists -- the ones who do simulations know perfectly well that weather parameters often have non-Gaussian statistics, with 1/f-like distributions being surprisingly common. Typical of the uncertainties take for example the bullet-summary of the Vecchi paper you cited: "Alternative interpretations of the relationship between sea surface temperature and hurricane activity imply vastly different future Atlantic hurricane activity." Looie496 (talk) 20:57, 7 September 2017 (UTC)

• Note that, unlike seismic stress, the energy which drives hurricanes (water temperature) does not simply accumulate until it is released in a hurricane. While this is somewhat true within a single hurricane season, each winter cools the water and "resets" the energy level. Thus, several years with no major hurricanes does not mean they becomes more likely, or less likely, than the long term average, on the following year. Global climate change, on the other hand, may do just that. StuRat (talk) 00:31, 7 September 2017 (UTC)

Right, this would not really due but the gambler's fallacy. Like heads or tails being ahead with coins. Perhaps the Atlantic multidecadal oscillation is not insignificant compared to the expected amount of random chance but I don't know the relative importances. Sagittarian Milky Way (talk) 01:08, 7 September 2017 (UTC)

• This blog post is relevant to both the previous climate change discussion and this one. It's a very narrow look at Tampa Bay, but provides an insightful look as well as links to further research. [5] 38.88.99.222 (talk) 13:42, 10 September 2017 (UTC)

Relevant articles are grey swan and black swan theory. 38.88.99.222 (talk) 13:44, 10 September 2017 (UTC)

Do rattlesnakes charge?

Looking around the web for advice on how to handle a rattlesnake that is blocking your trail, it seems that quite a few commentators advise not to throw rocks at it or poke it, even from a distance, on the grounds that you might provoke it to attack.

Are there actual documented cases of a rattlesnake (let's say one with an easy escape option, like gliding off the trail) charging someone who gently tried to get its attention with pebbles, or by nudging it with a trekking pole? By "charging" I mean not just striking, but running after a person farther than its striking distance.

The commentators mostly say to just wait, or go around. But sometimes there's no way around, and if the snake is enjoying the sun, it might be a long wait. --Trovatore (talk) 10:07, 6 September 2017 (UTC)

Most sites I can find say that rattlesnakes are NOT aggressive (that is, attacking unprovoked), but will take defensive action when they perceive a threat. These sites all state that in nearly all cases, attacks on people are provoked, and that defensive actions are often misinterpreted as aggression; that is people may not intend to provoke a rattlesnake but may accidentally do so, and in doing so may misinterpret defensive action by the rattlesnake as aggression (i.e. passing very close to a snake, stepping on it in leaf litter, backing it into an inescapable situation, etc.) See This from the US Department of Agriculture, This from National Geographic, Here from Brittanica.com, etc. --Jayron32 12:28, 6 September 2017 (UTC)

A rattlesnake can be surprisingly good at disappearing quickly and quietly when you look away. If you throw a bunch of rocks at a rattlesnake to make it go away ... then lose track of where it ended up ... then walking through the area could be interesting. Wnt (talk) 19:52, 6 September 2017 (UTC)

As a kid we used to catch them with my uncle (he made belts from their hide). Having personally caught several dozen of them by hand my observation is that they are most certainly not inherently aggressive animals. But they can also be very stubborn and will often prefer to stay put ("stand their ground") rather than flee. If provoked they can definitely be quite defensive, although typically using "feigned" charges/strikes. The best advice I can give you is to simply go around them. They seem to be fairly perceptive insofar as intentions go, so as long as you pass by them in a non-threatening way you really shouldn't have anything to worry about. Just don't get too close, and use common sense. And by all means, DO NOT THROW OBJECTS OR POKE AT THEM! I was bitten once as I grabbed one (badly aimed swipe) and it was extremely painful to say the least (some people have severe reactions to the venom, which can sometimes be fatal) so for safety's sake always exercise caution with these creatures. 73.232.241.1 (talk) 20:16, 6 September 2017 (UTC)

Well, your experience is interesting but doesn't seem directly relevant, since your hand was in striking range. I was asking whether they will pursue beyond their striking distance. --Trovatore (talk) 20:44, 6 September 2017 (UTC)

From my experience, no, they just aren't prone to chasing people around. But again, intention is the most important thing. If they sense that they're being actively stalked or if you try to interact with them even from a distance, they will often take up a defensive posture, make striking motions, or perhaps appear to chase after you (although I've never actually seen them do much of that myself). Otherwise, you could probably pass by it even within striking range and it wouldn't do a thing. They just tend to avoid confrontation. 73.232.241.1 (talk) 20:56, 6 September 2017 (UTC)

The nature of snakes is such that they really need to face their perceived attacker to be able to strike, and they can't really back up, so they either need to turn tail and run for it, or stand their ground. A defensive retreat isn't an option. Professional snake handlers seem to like to use a very long pole, not to poke them, but to put it under their coils and push them off the path. StuRat (talk) 20:26, 6 September 2017 (UTC)

Well, not exactly. If several people surround the snake, for example, their awareness seems to become rather heightened and they can readily shift around to strike from different directions. For that very reason our approach was to have just one person approach to catch the snake. That way, they leave their guard down somewhat and thus much easier (and safer) to capture. Also, while they don't move backwards per se, they can however undulate their bodies to easily move around in just about any direction, so just keep that in mind. 73.232.241.1 (talk) 20:46, 6 September 2017 (UTC)

OK, so here's the backstory. I ran into this little guy on a hike, going up to Mount Wilson. I would guess about two feet long, but could have been three, I suppose. He was sitting very still; I couldn't see that he was moving at all. There was no way around that didn't involve getting into striking range. Oh, I suppose we could have tried to bushwhack above or below, but the hill was steep and crumbly and full of poison oak.
Eventually I started to consider the idea that he might be a former rattlesnake, pining for the fjords. I tossed rocks (really pebbles) at him to test that theory, and hopefully to gently induce him to reconsider his location if he was alive. He flicked his tongue but made no other sign of having noticed.
Finally I reached out as far as I conveniently could with my right pole and gave him a gentle nudge or two. With no sign of hurry or distress, he glided off into the brush and left us alone.
Obviously this anecdote is not meant as advice to anyone; it's just my personal experience. I never felt that I was in danger. I was trying to find out if that perception was accurate. --Trovatore (talk) 21:25, 6 September 2017 (UTC)

Yes, they're generally very easy-going creatures (although their prey might beg to differ about that!). And probably due to the very fact that they are well-aware of their own defensive capabilities, they don't seem to be easily spooked by non-threatening gestures either, which paradoxically makes them much safer to be around then say a wild boar or something; when they retreat, they do so confidently and without much fanfare. Thanks for the pic, by the way, beautiful colors that one!73.232.241.1 (talk) 21:43, 6 September 2017 (UTC)

Yes, a good comparison might be a cat. Both are absolutely deadly to mice, but will usually run from people, or watch from a safe distance, unless cornered, then watch out, and be prepared to feel the fangs (and claws in the case of the cat). Another commonality is that both might cuddle up to you while you sleep, for your body heat (which might be quite alarming in the case of the rattlesnake, and even in the case of the cat, if you're a dog person). StuRat (talk) 21:55, 6 September 2017 (UTC)

• The crucial fact here is that a rattlesnake is almost defenseless unless coiled, so when threatened it coils up and is very difficult to persuade to uncoil except by giving it something to strike at. Consequently throwing rocks is not useful unless you can kill it, which is not easy. Poking a coiled rattlesnake with a trekking pole is dangerous -- you're too close. The proper solution is to find a tree branch at least ten feet long and use it to push the snake off the trail. It absolutely will not charge you, because as I said when "charging" it is uncoiled and therefore quite vulnerable. I have used this approach myself when I encountered a very large coiled rattlesnake in the middle of a trail on Mt. San Jacinto. Looie496 (talk) 23:53, 6 September 2017 (UTC)

  So as you can see from the picture, this one was not coiled, just "folded" once, as it were. --Trovatore (talk) 00:16, 7 September 2017 (UTC)

Would throwing cold water on it make it go away to seek out a warm place? Count Iblis (talk) 01:47, 7 September 2017 (UTC)

Possibly, but you would need a large supply of cold water, which seems unlikely on the trail. Also, you would need a way to spray the snake from out of range. A squeezable water bottle with a small hole on the top (for a straw) might work. Of course, you don't want to use up your water supply, either. StuRat (talk) 02:43, 7 September 2017 (UTC)

No, rattlesnakes don't charge, they bite for free (if the snakes are lawyers, they call it "pro bono"). StuRat (talk) 02:56, 7 September 2017 (UTC)

"I've never had an accident." "Weren't you bitten by a snake once?" "That was no accident - he did it on purpose." ←Baseball Bugs ^{What's up, Doc?} carrots→ 03:07, 7 September 2017 (UTC)

September 7

Pill so that two people don't end up catching feelings

Is there any proposal for a pill that prevents people from catching feelings if they have casual sex? In other words an emotional 'condom'. — Preceding unsigned comment added by Uncle dan is home (talk • contribs) 01:43, 7 September 2017 (UTC)

The obvious idea is to block oxytocin; searching for block oxytocin pulls out refs like [6][7][8] - though they go further afield. (I should note for those below who still seem unbelieving of the possibility of such a thing that these are actually references, if not real science references, that seriously talk about "anti-love drugs") A repeated suggestion involves SSRIs. Seems like one of the most useless strains of witchcraft I've heard of... Wnt (talk) 02:39, 7 September 2017 (UTC)

(ec) Maybe an oxytocin antogonist might have that effect, but it would also make sex less enjoyable. StuRat (talk) 02:40, 7 September 2017 (UTC)

Meditate on crying babies?^[Humor] —PaleoNeonate – 12:22, 7 September 2017 (UTC)

Isn't marriage enough without the babies? 209.149.113.5 (talk) 17:45, 7 September 2017 (UTC)

Feelings are not a disease. I'm not sure the question is answerable as asked, because it's based on a false premise. There is no "cure" for feelings, you don't "catch" them. --Jayron32 13:51, 7 September 2017 (UTC)

Actually, many people may develop suicidal thoughts and feelings because they have recently taken prescription drugs recommended by their own physician. So, feelings can be a symptom of disease or abnormal psychology. 50.4.236.254 (talk) 00:30, 8 September 2017 (UTC)

They may be a symptom, but they are not the disease. The question really is whether there's a drug that could make you stop having feelings. That goal, in itself, sounds depressing. ←Baseball Bugs ^{What's up, Doc?} carrots→ 02:12, 8 September 2017 (UTC)

Hypoesthesia and prefrontal lobotomy may be of interest. That is surely a way to stop feeling and stop the conscious awareness of feeling! There are also various drugs that reduce sex drive. 50.4.236.254 (talk) 03:06, 8 September 2017 (UTC)

Obviously, you (random reader) should not perform lobotomy on anyone including yourself. Folks, please remember that we have to assume very very stupid people may be reading what you post here. Tigraan^{Click here to contact me} 17:30, 8 September 2017 (UTC)

Yes, but think of how many more of us would be amused to watch the video. ;) Wnt (talk) 18:02, 8 September 2017 (UTC)

On the contrary, I would hope most of us would be appalled, and would hope that most of the participants here would not find crude debilitating dehumanizing surgery amusing. - Nunh-huh 18:09, 8 September 2017 (UTC)

Atosiban blocks the action of oxytocin and vasopressin. Oxytocin is involved in a number of roles including anxiety as it relates to emotional attachment. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1621060/ Perhaps atosiban could reduce the feelings of attachment following a sexual encounter. 208.90.213.186 (talk) 20:59, 8 September 2017 (UTC)

"natural products"

John Cornforth's certificate of election to the Royal Society includes the phrase "Miscellaneous work on natural products". What does the RS mean by the phrase? Carbon Caryatid (talk) 07:24, 7 September 2017 (UTC)

• Link to the source from the article. Tigraan^{Click here to contact me} 07:58, 7 September 2017 (UTC)

"Boyhood rambles in the bush inspired Cornforth's interest in natural products, and he began graduate studies at the University of Sydney. A number of his early papers were on the constituents of Australian plants, such as the caustic vine (Sarcostemma australe)". [9] So presumably it means naturally occurring compounds found in plants. Alansplodge (talk) 08:17, 7 September 2017 (UTC)

Of course, we have an article: Natural product, which explains all. I have wikilinked the phrase in our John Cornforth article. Alansplodge (talk) 08:24, 7 September 2017 (UTC)

That article says "In the broadest sense, natural products include any substance produced by life." That doesn't seem broad enough to me. I would include products like pumice, which are not produced by life. I would also exclude products produced in a lab, by people (life), like einsteinium. StuRat (talk) 14:44, 7 September 2017 (UTC)

Erm, which organism makes pumice? And what is natural about an artificially produced element? You can use any definition you want to use, but the definition in the article is the one people actually in the field use, and makes a hell of a lot more sense than what you are proposing. In fact, it's probably a wider definition than most chemists would use, as is clearly stated in further paragraphs. Fgf10 (talk) 15:22, 7 September 2017 (UTC)

Per Fgf10, the definition is what the definition is. It's already established. Just because YOU, StuRat, wish to create a new definition doesn't mean the already existing definition is wrong. See etymological fallacy. --Jayron32 16:00, 7 September 2017 (UTC)

I am stating that the scientific definition is at odds with the common (and likely legal) use of the term. If somebody wants to sell a pumice stone and puts "Natural product" on the label, nobody will claim false advertising. If our article excludes the common and legal defs, then that's a mistake. StuRat (talk) 16:03, 7 September 2017 (UTC)

Well, the question is specifically about the use of the term by the Royal Society, "the independent scientific academy of the UK and the Commonwealth", [10] so I believe that the narrow, scientific definition is the one we're looking for (and seem to have found). Alansplodge (talk)

For the Q, yes, but the article should have sections for non-scientific usages of the term, too. StuRat (talk) 15:29, 10 September 2017 (UTC)

Burst lithium battery pack

When a lithium battery pack is burst, noxious fumes are released. What are the chemical constituents of the fumes? 38.88.99.222 (talk) 10:28, 7 September 2017 (UTC)

There is little good work in this field as yet. Battery technology is changing rapidly and we don't have enough carefully studied hands-on experience. Large battery fires have been events like the M6 waste storage yard fire where the priority was to control a large blaze spreading to other materials, like solvents, rather than looking at the details of the battery fumes. The main constituents of lithium cells (which covers a broad range of types) are lithium salts such as lithium cobaltite which are not significantly hazardous. The main problem seems to be from a minor constituent of the electrolyte, lithium hexafluorophosphate (maybe 1% of the cell content mass). As the attentive will have already noticed, "fluoro-". So the fumes from that burning contain a small quantity of hydrofluoric acid, and that's never a good thing.

There's also the risk that such a cell burning is hot, in the middle of a piece of modern technology. So there could be all sorts of polymers, maybe fluorinated, around it. The fume risk might be more from the container than the cell. Andy Dingley (talk) 10:49, 7 September 2017 (UTC)

References

Hurricane IRMA impact data (observed, not forecast)

I'm looking for tabular data or shapefiles of observed, not forecast Hurricane Irma wind speeds. All the NOAA data I can find is impressive looking forecasts. Where should I look? Hayttom (talk) 14:30, 7 September 2017 (UTC)

[11], column 9, in knots. This dataset is a best estimate of historical behavior based on a mix of models, satellite, and such direct observations as may exist. If you strictly want observations only then you probably have to track down the hurricane hunter plane data and whatever land-based sites it happened to pass over. Dragons flight (talk) 14:36, 7 September 2017 (UTC)

OP here. I've found what I need (sample below from 0300 Zulu today) in this document available from this page.

HURRICANE CENTER LOCATED NEAR 21.3N 72.4W AT 08/0300Z POSITION ACCURATE WITHIN 10 NM

PRESENT MOVEMENT TOWARD THE WEST-NORTHWEST OR 290 DEGREES AT 14 KT

ESTIMATED MINIMUM CENTRAL PRESSURE 920 MB EYE DIAMETER 20 NM MAX SUSTAINED WINDS 145 KT WITH GUSTS TO 175 KT. 64 KT....... 65NE 45SE 35SW 55NW. 50 KT.......100NE 70SE 50SW 80NW. 34 KT.......160NE 120SE 80SW 150NW. 12 FT SEAS..540NE 240SE 90SW 480NW. WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT.

I'm parsing it into ArcGIS. Hayttom (talk) 06:39, 8 September 2017 (UTC)

Our original question seeks "observed, not forecast" wind speeds. Oh boy! If you're a weather geek, it's time to become educated about the most strict interpretation of weather terminology: weather information is categorized into three distinct types of weather information: observations, analyses, and forecasts.

Quoth the canonical text: "Observations are raw weather data collected by sensor(s). The observations can either be in situ (i.e., surface or airborne) or remote (i.e., weather radar, satellite, profiler, and lightning)."

Categorically, "Winds Aloft" fall under the definition of the category of a forecast, not an observation.

Surface wind observations, on the other hand, are available: if you want only observations and no forecasts, try the official Aviation Weather website - click on "Observations" and select METARs for a graphical view of all the reporting stations.

If you want text data, the observation prefixes the forecast in the textual data viewer tool: so click on the Forecasts menu and select TAF, and type in the stations you want.

For example, on Wednesday, I got this fantastic bit of amazing weather from the surface observation at TNCM:

TNCM 061121Z 0612/0712 300120G140KT 1SM +RA BKN015 OVC030

That is an observed surface wind, generally from the north-west, at 120 knots wind speed (sustained for a 2 minute period), with gusting up to 140 knots.

Here's a link for decoded current conditions; here are recent hourly data dumps; and you can figure out how to check other surface stations by modifying those URLs or navigating around on the NOAA weather websites.

If you care about the technicalities - here's a free book you ought to read: Advisory Circular 00-45H: Aviation Weather Services. (The full book is a PDF link at the bottom of that page; this book gets updated every few years, so check for the most current version).

This book provides information on all the operational weather products that the National Weather Service publishes. This book defines the standard formats: refer to it when you want to decode the various hard-to-read weather text products.

It's pretty darned near impossible to observe the wind at every point in three-dimensional space; we rely on forecast and analysis to figure out what the wind speed is in the hurricane. So if we're using the strict definitions, you won't find many hurricane wind observations - except for the occasional PIREP, or pilot weather report from an aircraft that is intentionally flying into the hurricane - that would be, in specific, one of the Air Force or NOAA hurricane hunters like the 53rd Weather Reconnaissance Squadron or the NOAA P-3D fleet. You can find those observation reports - if any were made - at the weather service's ADDS Aircraft Reports graphical view webpage.

Since we're mincing words about "forecast" and "observed" data - here's a note about the legal-ese definition of "operational" - when a weather product is "operational," it means there is some legal obligation by the government to provide it, usually mandated by some law, regulation, an act of Congress, a legally-binding letter of intent, and so on. Operational weather products adhere to standard methodology and terminology - and is generally executed in a manner I would describe as flawless. Things like surface weather observations and winds-aloft forecasts are both operational. For example - if you had to stand in front of a judge and testify that the wind was 120 knots on a specific day, you would want to cite a reliable source - like an operational weather observation - and if one was not available, you would want to cite an operational forecast. This matters if there is any reasonable doubt about the actual wind speed. Truth is a fleeting entity! But if you have an operational forecast, it's nearly as good as an actual observation, and in some cases, it's still better than a non-operational observation!

Every once in a while, you may find "non-operational" weather information - in other words, the weather service might have a wind measurement obtained by "unregulated" or "undocumented" methods - like some machine that the research lab has churned out, but does not yet have any proverbial Government "stamp of approval." Those data products are rarely spread far and wide to the public; but you can find it in published research, at weather conferences, and so on.

So, why do you care? Well, suppose you are constructing a big data aggregation database - it is nice to know that your data is standardized and every data collection station has been formally, procedurally verified. The machines and measurement sensors are standard; the computer software is standard; and so on.

On the other hand, suppose your house got blown away by a hurricane, and your life insurance policy didn't cover you in the event that you failed to evacuate during winds forecast to be stronger than ... well, you get the idea.

Nimur (talk) 15:41, 8 September 2017 (UTC)

Past eclipse weather

That question reminds me: are reports available showing the weather (cloud cover in particular) actually observed at points all along the recent solar eclipse track, to compare with early general predictions like this or with specific forecasts that were published in the days before the eclipse? And similarly for other eclipses of the past. All I could find by looking in newspapers online this time is reports on places that each paper thought its readers would be intrested in, or reports on people's activities that don't actually mention the weather, which is not surprising. --69.159.60.147 (talk) 22:28, 7 September 2017 (UTC)

September 8

Ball valve

Right now the construction of my pilot plant is going more-or-less OK, but there's one slight problem: the shutoff valves to the main pump are frozen solid in the fully open position after almost a whole year of disuse. The one on the discharge side (which is the more critical) I was able to wiggle free, but the one on the suction side (being a cheaper brand) remains frozen despite my utmost efforts to the contrary, as does the only spare for it. So can anyone advise me on how to free a jammed ball valve (if possible, without introducing any chemical contaminants into the piping)? 2601:646:8E01:7E0B:4E8:FDC:7D20:30AB (talk) 10:59, 8 September 2017 (UTC)

What is your pilot plant for? Blooteuth (talk) 12:35, 8 September 2017 (UTC)

Synthetic turquoise. 2601:646:8E01:7E0B:4E8:FDC:7D20:30AB (talk) 06:41, 9 September 2017 (UTC)

An impact driver might loosen it - but it might also break the valve handle and stem (and/or the pipe joints). Moving it every so often so it would not seize up would been preferable, but a little too late for that now. WegianWarrior (talk) 12:38, 8 September 2017 (UTC)

For the same drawbacks but less expense (if you don't own an impact wrench), you might try increased the lever arm length to get more torque. Putting a piece of pipe over the handle to create a cheater bar might work, but they are dangerous, so consider the alternatives listed there, too (and kicking the end of the cheater bar instead of putting your body weight into it is a bit safer). Or just use a large pipe wrench to grab hold of the handle (other types of wrenches typically aren't as large). There's also changing the temps of the inner and outer materials, in opposite directions, to get one to expand and one to contract, but that's tricky to do. StuRat (talk) 15:25, 8 September 2017 (UTC)

You really only have three choices. [1] Drop your unneeded "without introducing any chemical contaminants" requirement, remove the valve from the system, soak it in a penetrating oil for a few days, then clean it before reinstalling. [2] Hit it with a blowtorch and see whether it comes unstuck or whether you just ruined your valve with a blowtorch. [3] Apply more and more force until it either breaks loose or simply breaks, causing you to buy a new one.

There is another lesson to be learned here. From now on, whenever you build a system, make a maintenance plan and follow the plan. In your case, one of the items should be moving every valve once every two weeks. Make a checklist with things like "inspect pipe 23A for external corrosion" and "clean air filters on Unit 17B". It's part of the difference between being a professional and being a garage shop. --Guy Macon (talk) 15:55, 8 September 2017 (UTC)

Thanks! I think I'll go with #3 -- I happen to have a big pipe wrench, and I'll use it. (#1 is kind of hard to do, given that the valve is a one-piece design, and #2 is dangerous because the plant is housed in a wooden building -- you don't want to use a blowtorch around wood if you don't absolutely have to!) 2601:646:8E01:7E0B:4E8:FDC:7D20:30AB (talk) 06:41, 9 September 2017 (UTC)

I'm reminded of the time I had a car with a flat tire, tried to change it, and one bolt just would not come loose. I used the breaker bar method, and it still wouldn't budge with me pushing on the end of the rod. So then I jumped up and down on the end of it. That sheared the head off the bolt. At least I was able to change the tire then, and the spare stayed on just fine with 4 of the 5 bolts. StuRat (talk) 17:31, 10 September 2017 (UTC)

Vespula germanica

"V. germanica disperses at a rate of no more than 1000 m per year" — What exactly does that mean? And where does the name come from? Unfortunately, this is not really explained in the article. Best regards--Tuchiel (talk) 13:16, 8 September 2017 (UTC)

• Vespula comes from the same root as the word wasp, being the Latin word vespa. Germanica means "of Germany". --Jayron32 13:19, 8 September 2017 (UTC)

@Jayron32: Thanks. Yes, I already knew the meaning, but I wanted to know why they chose the term "germanica" as a reference to Germany.--Tuchiel (talk) 14:37, 8 September 2017 (UTC)

• The species was named by Johan Christian Fabricius, a Danish biologist, in 1793, undoubtedly because he observed them in Germany. As for the meaning of the sentence, it says that if you find these wasps in a given set of places at a given time, and then look around one year later, you probably won't find them more than 1000 meters away from the original set of places. Looie496 (talk) 14:43, 8 September 2017 (UTC)

@Looie496: Wouldn't that be actually an interesting / relevant complement to the article?--Tuchiel (talk) 14:57, 8 September 2017 (UTC)

I made an edit to that effect, linking to the biological dispersal article (though I am sure it could be better-formulated). Tigraan^{Click here to contact me} 17:22, 8 September 2017 (UTC)

Tuchiel's follow up query –". . . why they chose xxx . . ." – illustrates a widespread unconscious false assumption. Scientific names are not chosen by some overarching committee of worthies; they're (usually) chosen by the individual or (in more recent times) perhaps a team of authors who first published a scientific description of the species concerned. Often (though not always) they will have explained their choice, and its meaning in a vernacular language, in that description. Nearly all of the species of animals and plants in Europe (and many common ones elsewhere) will have been named by the 18th-century originator of the binomial system, Carl Linnaeus, or one of his near contemporaries and successors. {the poster formerly known as 87.81.230.195} 2.122.61.201 (talk) 23:51, 8 September 2017 (UTC)

Feynman Lectures. Exercises. Exercise 14-3 JPG

. .

...

14-3. The particle of Ex.14-1 moves from the point (0,-1,0) to the point (0,+1,0) on a frictionless track under the action of the force F (plus a certain force of the constraint). Find the work done by the force F if the truck is
a) A straight track along the y-axis
b) A circular track in the z-y plane
Is this a conservative force?

F=1.5yi + 3x²j - 0.2 (x²+y²)k

—  R. B. Leighton , Feynman Lectures on Physics. Exercises

In Solutions of 1965 and 1978 there are 2 different answers. I don't understand, why. It seems both are correct. They use another path to show that the force is not conservative : a circle path in x-y plane png.
1965:
$W=\int \limits _{M_{1}}^{M_{2}}F_{x}dx+\int \limits _{M_{1}}^{M_{2}}F_{y}dy=3\int \limits _{-1}^{1}x^{2}dy=3\int \limits _{-1}^{1}(1-y^{2})dy=4{\text{ J}}$

1978:
$W=\int \limits _{M_{1}}^{M_{2}}F_{x}dx+\int \limits _{M_{1}}^{M_{2}}F_{y}dy=1.5\int \limits _{M_{1}}^{M_{2}}ydx+3\int \limits _{M_{1}}^{M_{2}}x^{2}dy=$

$\textstyle 1.5\int \limits _{\pi }^{0}\cos ^{2}(\psi )d\psi -3\int \limits _{\pi }^{0}\sin ^{3}(\psi )d\psi =$

$\textstyle 1.5[{\tfrac {1}{2}}\psi +{\tfrac {1}{4}}\sin 2\psi ]_{\psi =\pi }^{\psi =0}-3[\cos \psi -{\tfrac {1}{3}}\cos ^{3}\psi ]_{\psi =\pi }^{\psi =0}=1.6{\text{ J}}$


$x=\sin \psi {\text{ , }}y=\cos \psi {\text{ , }}dx=\cos \psi d\psi {\text{ , }}dy=-\sin \psi d\psi$. Username160611000000 (talk) 15:23, 8 September 2017 (UTC)

• I think I understood. In first case the integral must be not $\textstyle 1.5\int \limits _{0}^{0}ydx$, but $\textstyle 1.5\int \limits _{0}^{1}-{\sqrt {1-x^{2}}}dx+1.5\int \limits _{1}^{0}+{\sqrt {1-x^{2}}}dx$.Username160611000000 (talk) 05:19, 9 September 2017 (UTC)

Sorry, it is impossible to help you as you did not formulate the problem that you are trying to solve with these integrals. Ruslik_Zero 18:15, 9 September 2017 (UTC)

Delay timer mains power

I want to create a circuit that has a delay timer so that it turns on after a certain amount of time, say 5 minutes. I have the timer dial from an old oven which is rated for mains voltage and turns the power on for the duration it is set for, then turns the power off. Can I just connect this to a relay so that when the timer turns off the relay switches the power to the other circuit on? Would this work or have I missed something important? 77.28.149.135 (talk) 16:12, 8 September 2017 (UTC)

It would work. But then for £1 or so from eBay, I can buy a modern module that does all sorts of timing, and has pushbutton start.

There's also the question of whether you want the relay on before the delay has been started. Your cooker timer would need an additional switch. Andy Dingley (talk) 19:04, 8 September 2017 (UTC)

It depends on whether the oven timer has normally open contacts and how they are configured to operate when idle and after the time delay expires. If you're having trouble figuring this out, you're strongly advised to not mess with the dangerous voltages involved, and you should follow the advice by Andy Dingley and buy a ready-made timing device that requires you to do no more than plug it in. If you cause a house fire by unapproved wiring, you may find that insurance will not cover losses, and you may put neighbours' lives at risk. Akld guy (talk) 22:17, 8 September 2017 (UTC)

Hey, I'm from the "burn your house down" school of cookery. Most of the stuff I've learned, I've had my trousers singed, if not quite on fire. Andy Dingley (talk) 00:45, 9 September 2017 (UTC)

The oven timer has a single-pole switch so that the wiring to your relay will be dangerously live to the mains all the time. I advise including a mains-powered red warning light to show when the countdown is in progress. Blooteuth (talk) 12:19, 9 September 2017 (UTC)

Did CO2 emissions end the Little Ice Age ?

We can read here:

"The data and simulations pinpointed the early onset of warming to around the 1830s, and found the early warming was attributed to rising greenhouse gas levels. This coincides with the early stages of the Industrial Revolution, in which large volumes of harmful greenhouse gases began to be produced."

"Dr Abram said the earliest signs of greenhouse-induced warming developed during the 1830s in the Arctic and in tropical oceans, followed soon after by Europe, Asia and North America."

This coincides with the end of the Little Ice Age. Count Iblis (talk) 20:02, 8 September 2017 (UTC)

Well, perhaps, but I'll stay uncommitted, given that such a mechanism clearly can't explain the Medieval Warm Period that preceded the Little Ice Age. I'm skeptical that human-caused greenhouse gas emissions were high enough in 1830 to account for this magnitude of change. Looie496 (talk) 13:54, 9 September 2017 (UTC)

Fortunately Science does not need simulations anymore since they started drilling ancient ice bodies to get Ice cores which contain an enclose exactly what mixture of air and even dust, ash and the radiation that was in our Atmosphere at a given time in the past. --Kharon (talk) 14:33, 9 September 2017 (UTC)

Huh? The lead investigator of the work, Nerilie Abram, is apparently well-known for ice core work. Rmhermen (talk) 16:14, 9 September 2017 (UTC)

I'm not much up to date on this, but there is (was?) a theory that LIA was really the onset of the next glacial, and that human-caused global warming stopped that. 93.139.41.72 (talk) 02:20, 10 September 2017 (UTC)

Neutron star collision at high speed, follow up question

What if two neutron stars collided head on with center of mass velocity of 99.90 percent of speed of light? Would that cause explosion or fragmentation of the neutron stars? Would a lot of neutrinos be created? (Could neutrinos conceivably carry away a major fraction of mass?)144.35.114.187 (talk) 22:40, 8 September 2017 (UTC)

Our article Supernova, Section 6.2 Core collapse, states at one point "About 10⁴⁶ joules, approximately 10% of the star's rest mass, is converted into a ten-second burst of neutrinos which is the main output of the event." Clearly, then, neutrinos can carry away significant mass in such stellar events. Without doing the numbers, I'd guess that the scenario you describe would be considerably more energetic than a supernova core collapse, that a very significant proportion of their masses would be converted to neutrinos, and that the two neutron stars would be entirely obliterated in something more spectacular than a mere supernova.

While Stellar collision#Neutron star collisions doesn't go into details, a simple google search finds this paper, but it's addressing a merger of two mutually orbiting neutron stars, rather than the extremely unlikely scenario of two independent neutron stars happening to collide, let alone the vanishingly unlikely one of them moving at such velocities (assuming the collision is natural and not the result of a Super-CERN type experiment by extremely advanced beings).

[Edited to add . . .] Continuing the analogy with CERN, I'd guess that such a collision might well result in some entirely new physics (just as high energy CERN collisions can result in hitherto unknown particles), so your "what if . . ." question may be inherently unanswerable. {The poster formerly known as 87.81.230.195} 2.122.61.201 (talk) 00:07, 9 September 2017 (UTC)

September 9

Action potential in rabbit's sciatica

I am looking for a picture of afferent and efferent action potentials in rabbit's sciatica. Is anything like this available on the web? Thanks --AboutFace 22 (talk) 00:19, 9 September 2017 (UTC)

Do you mean the rabbit sciatic nerve? In any case you'll need to be a bit more clear. It might help to give us a little information about what you would like to use this for. Looie496 (talk) 00:41, 9 September 2017 (UTC)

Sciatica is a pain symptom in the leg, associated with the Sciatic nerve. Afferent and efferent nerve fibers carry nerve impulses repectively towards and away from the Central nervous system i.e. brain and spinal chord. Here are references:

SCIATIC NERVE CONDUCTION VELOCITY AND LOCOMOTORY PATTERNS IN FROG, UROMASTIX AND RABBIT; Locating the target nerve and injectate spread in rabbit sciatic nerve block; Ultrastructural study of rabbit sciatic nerve regeneration; Nerve conduction and microanatomy in the rabbit sciatic nerve; Magnetic resonance microneurography of rabbit sciatic nerve; The toe-spreading reflex of the rabbit; NERVE STIMULATOR–GUIDED SCIATIC-FEMORAL BLOCK IN PET RABBITS; Effects of muscle relaxants on EEG, ABR and EMG in rabbits; Experimental EMG-anatomopathological study of rabbits; Sympathetic influences on the activity of the cerebral cortex (experiments on rabbits). Blooteuth (talk) 11:50, 9 September 2017 (UTC)

Thank you. Sure I got mixed up and I certainly meant "sciatic nerve." Thank you @Blooteuth. That's a wealth of information. --AboutFace 22 (talk) 13:07, 9 September 2017 (UTC)

Interaction between types of muscles

What kind of interaction can appear between types of muscles like the bulbospongiosus muscle and anal sphincter muscles and colon muscles in ejaculation? (Thanks.)--82.137.9.100 (talk) 12:02, 9 September 2017 (UTC)

I do not think muscle interacts with muscle, unless you are referring to the muscle fibers myosin and actin in the process of muscle contraction. Rather, it is the axon terminal of the motor neuron that interacts with skeletal muscle cells (such as anal sphincter and bulbospongiosus) at the neuromuscular junction. While ejaculation does involve the autonomic and somatic nervous systems, I don't think colonic smooth muscles are involved in ejaculation. [12] 50.4.236.254 (talk) 16:17, 10 September 2017 (UTC)

Genetics questions.

1. What is the mechanism that determines how many possible children you can have with different dna or genes. I know the final answer, it comes to around 69,000. That is, a the probability that the 2nd child will be genetically identical to the 1st is 1 in 69,000, which is also how many different possible combinations of genes or dna in children you can have altogether.

2. What's the mechanism that says, although you are exactly 50/50 of your parents, you are not necessarily 25/25/25/25 of your 4 grandparents. So that 50/50 of your parents is not a 50/50 of their parents. If I recall, the ultimate answer is "chromosome layering" but can someone get more specific on that, thanks. 12.130.157.65 (talk) 13:10, 9 September 2017 (UTC).

• The probability that two children will have identical DNA is virtually zero unless they are identical twins, and even then they may differ very slightly. The reason is genetic recombination, which mixes together the gene-pairs of the male and female parents in a very random way. Each egg and sperm cell sees a different pattern of recombination from every other. Genetic recombination is also the answer to your second question. Looie496 (talk) 13:46, 9 September 2017 (UTC)

• 1) There are many mechanisms. At the basic level of selecting 1 of each pair of chromosomes to go into each sperm (or egg), there are 23 chromosomes, giving 2^23 different possible chromosome combinations for each sperm and another 2^23 for each egg, or 2^46 ~= 7*10^13 different chromosome combinations for the children of a given 2 parents. (If I've done the combinatorics correctly.)--Wikimedes (talk) 02:45, 10 September 2017 (UTC)

• Once you get the DNA from your parents, for the most part, there is no "memory" of which DNA came from which parent. Therefore, there is no way to guarantee you will pass exactly half of that DNA from each parent on to your children. A thought experiment may help. Take two bowls of random marbles, and pour half of each into a third bowl. Now pour half of those out. What guarantee do you have that half came from each of the original two bowls ? StuRat (talk) 02:56, 10 September 2017 (UTC)

Incorrect, genomic imprinting. Fgf10 (talk) 08:38, 10 September 2017 (UTC)

According to that article: "For the vast majority of autosomal genes, expression occurs from both alleles simultaneously. In mammals, however, a small proportion (<1%) of genes are imprinted, meaning that gene expression occurs from only one allele." So, modify my example to show one marble in each bowl was labelled to show which parent it came from. This doesn't change the ability to guarantee grandparents each contribute DNA equally to their grandkids. They would ALL need to be labelled to do that. StuRat (talk) 15:27, 10 September 2017 (UTC)

Your statement "Once you get the DNA from your parents there is no "memory" of which DNA came from which parent." is incorrect. Nobody said there is no equal contribution, but there is clearly a mechanism for determining the origin of each chromosome (a 'memory'). Also, this is not just a scientific curiosity, it is the basis for a number of diseases, as stated in the article. Fgf10 (talk) 16:43, 10 September 2017 (UTC)

OK, I've added "for the most part" to my original statement. StuRat (talk) 18:09, 10 September 2017 (UTC)

Also of interest may be Population viability analysis and Minimum viable population —PaleoNeonate – 03:00, 10 September 2017 (UTC)

• The number seems to be a lot higher than that. It would be 2⁴⁶ if the chromosome were a faithful copy of a prior chromosome, which is (almost always) true during Mitosis. However, gametes are produced by a two-stage process that includes Meiosis, Where the genes within each chromosome pair are swapped around at the level of (approximately) the individual gene. So a gamete selects (very roughly) half of each of 20,000 or more genes, not half of each pair of 23 chromosomes, so the chance of identical gametes is more like 2^-20,000 and the chance of identical non-twins is 2^-40,000. -Arch dude (talk) 05:13, 10 September 2017 (UTC)

You're dramatically over-estimating the number of chromosomal crossovers per meiosis. It's at least two, close to three orders of magnitude lower than the number of protein-coding genes. See here. "Genes within each chromosome pair are swapped around at the level of (approximately) the individual gene" just isn't true. Adrian J. Hunter^{(talk•contribs)} 06:03, 10 September 2017 (UTC)

This is true for each crossover, but there are millions of sperm per male, and each crossover event is (sort of) independent. Therefore, we cannot simply say that there are 23*2 separate units to choose from (i.e., 2⁴⁶ different sperm possibilities.) Instead, the total number of possible unique sperm genomes from a single father is closer to the number I gave. I will admit that the 20,000 number is a guess about the total number of possible crossover points. -Arch dude (talk) 17:17, 10 September 2017 (UTC)

Note that cells contain mitochondria, which are transmitted only through the mother. 2A00:23C1:3180:B601:FC37:C608:7C91:52D6 (talk) 11:57, 10 September 2017 (UTC)

True, but not relevant to the question. you will have identical mitochondiral DNA with your mother and with all your siblings. This does not affect the number of possible chromosomal combinations -Arch dude (talk) 17:17, 10 September 2017 (UTC)

Feynman Lectures. Exercises. Exercise 14-6 JPG

. .

...

14-6. Often, a capacitor consists of two (metallic) bodies, equally and oppositely charged. The capacitance C is then defined as the ratio of the charge on one body divided by the potential difference between them:

C = Q / (Φ2 - Φ1) (Farad)

Find the capacitance of a pair of concentric spherical shells, of radii A and B.

—  R. B. Leighton , Feynman Lectures on Physics. Exercises

According to the Ch. 14-5 and Eq. (14.6), the potential of a point charge $\phi (x)=+{\tfrac {Q}{4\pi \epsilon _{o}x}}$. I assume that inside outer shell difference of its potentials = 0, so only inner shell is counted. Then difference of the potentials will be
$\phi (R)-\phi (r)={\tfrac {Q}{4\pi \epsilon _{o}R}}-{\tfrac {Q}{4\pi \epsilon _{o}r}}$
,where R = radius of outer shell;
r = radius of inner shell.

$\phi (R)-\phi (r)={\tfrac {Q(r-R)}{4\pi \epsilon _{o}Rr}}$

The difference and so the capacitance are negative . Is it ok? Answer gives C = 4πε_oAB/(B - A).Username160611000000 (talk) 13:30, 9 September 2017 (UTC)

The sign of potential difference obviously depends on what you subtract from what. Ruslik_Zero 18:06, 9 September 2017 (UTC)

The capacitance was negative only because you chose the inner shell (with higher potential) as reference, but Feynman's expression "potential difference between [the shells]" does not stipulate that. If you allow A = radius of inner shell and B= radius of outer shell the textbook answer applies. Blooteuth (talk) 19:05, 9 September 2017 (UTC)

September 10

Standard-Model Extension

Can someone explain this in simpler terms? Am I right in assuming that if Lorentz symmetry is broken, things can/do have an absolute velocity, position, orientation etc.? What is "dynamical" symmetry breaking? 93.139.41.72 (talk) 02:23, 10 September 2017 (UTC)

It means that if there existed some background static and spatially homogeneous vector or tensor field, it would be possible to measure absolute velocity and orientation relative to it. Such a field can appear as a result of some interaction within an initially Lorentz invariant theory - dynamically. So, Lorentz violation is fictional because the theory remains Lorentz invariant. For instance, if you are inside a large volume and there is a constant and homogeneous magnetic field inside it created by currents at the large distance from the observer, one may (without any information about what happens at large distances) conduct some experiments and conclude that there is indeed a preferable direction. Ruslik_Zero 18:34, 10 September 2017 (UTC)

Just in case you missed it: dynamical symmetry breaking 92.18.64.254 (talk) 20:21, 10 September 2017 (UTC)

If the tech level/population/GDP/Milankovitch factors/Sun/biosphere etc. stopped evolving in 1749 how long would it take for CO2 to rise 1ppm?

Would the anthropogenic fire/cow flatulence etc. carbon just go in the carbon sinks and the CO2 ppm in the atmosphere would never rise? Would this cause any ocean pH changes measurable with 2017 instruments? (our 2017, they're still using horses and buggies in this timeline's 2017 remember) Sagittarian Milky Way (talk) 03:08, 10 September 2017 (UTC)

The CO₂ level would level off at a lower level, but what that level would be and when it would level off I can't say. StuRat (talk) 03:13, 10 September 2017 (UTC)

• Too many variables, I think. Civilizations at that tech level tended to grow in population until the available land was all under cultivation. Examples include Italy, Greece, India, China, and England. If we project forward from 1749, humanity would have cleared the forests everywhere by now (except possibly for parts of Africa which are protected by diseases). The effect on CO₂ levels is hard to analyze. Also that tech level still allow for coal mining, which would be economically attractive as the forests disappeared. This was already happening in England by then.-Arch dude (talk) 04:52, 10 September 2017 (UTC)

The Black Death in Eurasia followed by the huge mass deaths in South and then North America from smallpox and other diseases are thought to have been one of the major contributors to the beginning of the Little Ice Age because they caused CO₂ to drop due to reforestation. The reforestation would be pretty rapid but the effect on temperature would be much slower, there would be a drop in CO₂ and then it would rise to near its former level as in 1400 over a couple of hundred years. So yes I believe in 1749 you'd be looking at CO₂ rising again so I guess they should only have taken about twenty years to rise 1ppm at that time. I'd say 1749 was about the beginning of the modern world so yes you are cutting out a lot of stuff never mind other factors that contributed to the Little Ice Age. One would really need a climate scientist to model it to get something reasonable but there are a lot of unknowns. Dmcq (talk) 11:48, 10 September 2017 (UTC)

Not an answer to your question, but memorably Svante Arrhenius estimated around the year 1900 that it would take about 3000 years to increase CO2 concentrations by 50%. Of course, we found many new uses of fossil fuels since 1900. Dragons flight (talk) 19:27, 10 September 2017 (UTC)

Virus vaccines

Thanks for the input! Nyttend (talk) 03:28, 10 September 2017 (UTC)

Measles

According to File:Measles vaccination coverage world.svg (data from 2010), Austria's vaccination rate was lower than that of countries like Chad, Iraq, and the Democratic Republic of the Congo. Why is their rate so low?

According to the german wiki:

In Österreich werden zwei Teilimpfungen gegen Masern-Mumps-Röteln ab dem vollendeten 9. Lebensmonat mit einem Mindestabstand von vier Wochen empfohlen. Bei Schuleintritt bzw. mit vollendetem 12. Lebensjahr soll der Impfstatus (Impfpass) kontrolliert werden. Fehlende Impfungen können in jedem Lebensalter kostenlos nachgeholt werden.[73] Eine Erhebung des Gesundheitsministeriums aus 2016 ergab, dass über 95 Prozent der 6-jährigen Kinder zumindest einmal gegen Masern geimpft sind. Bei den 2- bis 5-jährigen Kindern beträgt die Durchimpfungsrate jedoch nur 92 Prozent, zudem sind etwa 10 Prozent davon nur einfach anstatt zweimal geimpft.[74]☂[75]

Of the 6 year olds, 95% have received the vaccine at least once, according to 2016 data. Of the 2 to 5 year olds, 92% have received the vaccine at least once, 82% twice. It doesn't seem as dramatic as the map suggests. Maybe confusion over the exact meaning of vaccination (once or twice) or the age at which vaccination rate is measured. PiusImpavidus (talk) 09:45, 10 September 2017 (UTC)

The vaccination rate could have changed. New WHO data seems to confirm this. Ruslik_Zero 18:15, 10 September 2017 (UTC)

Chicken pox

According to [13], approximately 1% of individuals vaccinated with chicken pox will develop symptoms similar to that of an ordinary low-grade infection, and it's possible for them to develop shingles late in life. Have any cases of shingles been observed in those who were vaccinated without developing symptoms of a chicken pox infection? I'm not clear whether it's possible just in those who develop symptoms or in all those who are vaccinated.

Varicella vaccine gives some information. I'm pretty sure it's possible, because the varicella vaccine is a live vaccine. You're being deliberately infected, just with a weakened strain of the virus, and varicella, once acquired, hangs around for life in your cells (as do all of its family, the herpesviruses), and its reactivation is what causes shingles. If anything, I'd think people who have a reaction should be less likely to develop shingles, because it means their immune systems were more strongly activated by the vaccine. --47.138.161.183 (talk) 05:52, 10 September 2017 (UTC)

You can read this. Ruslik_Zero 18:19, 10 September 2017 (UTC)

Irma in Florida

I am wondering about the hurricanes. There is an article in Wikipedia that tries to explain it all.[14]. It seems the following it clear. The earth rotation linear velocities differences at different latitudes create cyclones. Had the earth been a cylinder no cyclones could have happened, right? Heat coming from the ocean is needed too. It is an enormous angular momentum after all. How come Irma hit Cuba, touched it a bit and turned North to Florida? Why? Where is the force that did it? Logically it would have to continue to the East coast of Mexico.

In the Atlantic the hurricanes travel West, in the Pacific they seem to travel East and in the Indian subcontinent they definitely travel East. Why?

In Jupiter the red spot (a hurricane) is said to have existed for 350 years. How did they determine it? --AboutFace 22 (talk) 21:08, 10 September 2017 (UTC)

Answering just the last question: see Great Red Spot. It has been seen since 1830, and is believed to be the same spot that was first observed over 350 years ago, but the record of observations is not continuous. It might be only about 190 years old, or it might be thousands of years old. --69.159.60.147 (talk) 21:23, 10 September 2017 (UTC)

Hurricane Irma's recurvature is largely due to forces exerted on the system by other areas of atmospheric pressure, particularly a high-pressure "ridge" over the North Atlantic known as the Bermuda High. See this Washington Post article for a summary.

Atlantic, Indian, and Pacific (and South Atlantic) tropical cyclones all predominantly travel westbound, not eastbound, though recurvature is not uncommon in all basins as systems move away from the equatorial trade winds, as per our article.

Jupiter's Great Red Spot is dated via continuous observation for ~190 years, and via inference from observations of a similar phenomenon (commonly assumed to be the same formation) dating back to 1665, as per our article. — Lomn 21:24, 10 September 2017 (UTC)