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June 17

Mount Everest reportedly moved 3 cm in April earthquake -- how was the measurement done?

It was reported in the news that Mount Everest was moved by 3 cm in the April earthquake. How was that kind of measurement done? --173.49.9.102 (talk) 03:47, 17 June 2015 (UTC)

Reports I've seen say it was using radar from a European satellite (see Talk:Mount Everest#Mount Everest Shrinkage for discussion of refs). DMacks (talk) 04:07, 17 June 2015 (UTC)

We have an overview article on satellite geodesy, the use of satellite radio data to accurately measure position. The most popular techniques use the GPS or GLONASS satellite constellations, but many other techniques exist (including RADAR altimetry, RADAR interferometry, LIDARs, and lots of other types of measurements and data analyses). In particular, because the recent "3 cm" measurement was conducted by Chinese researchers, it is not clear whether they would use GPS or some other satellite constellation (for example, 北斗卫星导航系统 satellite constellation). The institute where this research was conducted was the Institute of Geology, China Earthquake Administration, and the data was published in a press release on June 15, 2015: 珠峰地区10年位移40厘米上升3厘米 by the National Administration of Surveying, Mapping, and Geoinformation. The data was collected as part of the Crustal Movement Observation Network of China (CMONOC). The English language webpages of these organizations do not presently contain up-to-date information. It would be great if a fluent reader of Chinese can track down the complete report and provide a link. However, many English-language newspapers have provided summaries of this report, e.g. Mount Everest shifted 3 centimeters by Nepal earthquake.

NASA JPL hosts Crustal Movement Observation Network of China and its Phase II Project, and that suggests that the Chinese CMONOC researchers are using American GPS satellites and a network of ground stations in China, plus sophisticated data post-processing, to produce high-accuracy geodesy; but that report is nearly ten years old (and pre-dates BeiDou-2).

Contrast this to data and a news brief published by ESA: Nepal Earthquake on the RADAR (April, 2015). Those data and news stories are available from ESA in English; and they estimate a different vertical and lateral shift.

Nimur (talk) 05:06, 17 June 2015 (UTC)

Thanks for the references. They make interesting reading. --173.49.9.102 (talk) 10:49, 17 June 2015 (UTC)

healthcare costs in the USA

Why do healthcare costs get so high in the USA without insurance? They don't get that high (over 40usd) in other countries especially in emergencies. — Preceding unsigned comment added by 2001:268:D003:CD21:D39:C25C:721A:D94A (talk) 04:46, 17 June 2015 (UTC)

This should be moved to the humanities desk, but I'll give an answer first. In the US medicare/medicaid do not pay enough to cover the cost of treatment, so hospitals must bill everyone else more. Large insurance companies know that and negotiate them down, hospitals accept it since they at least make something. An individual has no bargaining power and hospitals bill as much as they can. That said, you don't have to actually pay that much, just don't pay for a month, then when you get a bill call and negotiate. They will accept a lower amount - they don't really expect anyone to pay the high amount it's just a number they use for negotiating with insurance companies, not a real figure. Ariel. (talk) 07:11, 17 June 2015 (UTC)

Beware of edging into legal areas, especially as the insurance laws and regulations vary state by state. ←Baseball Bugs ^{What's up, Doc?} carrots→ 08:52, 17 June 2015 (UTC)

Yea, it's like the suggested retail price. They don't seriously expect many to pay that much, but they give it a try anyway. There is the occasional exception, though, where they take people to court to try to collect some absurdly high bill, or at least report them to a credit agency and ruin their credit. StuRat (talk) 14:29, 17 June 2015 (UTC)

Two relevant articles are Moral_hazard and Principal-agent_problem. OldTimeNESter (talk) 12:20, 17 June 2015 (UTC)

Health_care_in_the_United_States and Health_care_finance_in_the_United_States are some additional relevant articles. SemanticMantis (talk) 14:27, 17 June 2015 (UTC)

The cost of healthcare in America is an exaggerated figure. It is primarily based on what healthcare asks for, not on what insurance companies or actual patients pay. My healthcare was practically free for as long as I can remember. I grew up very poor. My family had no insurance and we couldn't pay doctor's bills. So, the doctor would use a "sliding scale" and usually charge no more than $20-$30 for a family visit. I remember having free visits when we couldn't afford any payment at all. I have a job with insurance and now pay $40 copay. My brother was still uninsured and used a sliding scale until the Affordable Care Act shut that down. Now, he has to get insurance and pay a copay (which I doubt he has done). So, it is very possible that people are now paying more, but by increasing cheap insurance usage, the apparent "cost" is going down. 209.149.113.240 (talk) 15:21, 17 June 2015 (UTC)

To that point: another detail not commonly mentioned: in the United States, healthcare cost collection rate is astonishingly low. ACA reports only 15% of debt owed to hospitals, and 21% of debt owed to non-hospitals, is ever collected. Astonishingly lower statistics emerge if you track down payment rate within, say, the first 24 months; or if you require payment of the total amount. This means that on average, four of five dollars billed for healthcare are never paid in any form whatsoever in an American hospital: neither private nor public insurance, nor by way of direct payment. (The same statistic, by a different metric: almost 10% of gross hospital revenue is written off as a loss). The majority target of healthcare collection agencies is actually insurance companies, not individuals. Amazingly, American laws protecting privacy mean that hospital collections departments can not trivially access healthcare records, so billing is nearly impossible, and tracking delinquent bills (at a 15% success rate!) is usually more expensive than leaving the debt unclaimed.

A key takeaway is that in American healthcare, a dollar billed is a completely different entity than a dollar paid.

Nimur (talk) 15:26, 17 June 2015 (UTC)

US doctors earn a lot more per working hour per GDP per capita than doctors in other Western nations. Count Iblis (talk) 15:52, 17 June 2015 (UTC)

Citation? I see a lot of health data and I don't see many rich doctors. I see a lot of rich insurance companies and a hell of a lot of rich medical lawsuit lawyers (and insanely rich politicians). 209.149.113.240 (talk) 17:46, 17 June 2015 (UTC)

I'll dig up a few articles, but from what I remember, doctors earn more per capita per person in the US than doctors in other countries, but then in the US people with similar skills earn similarly higher wages as compared to the GDP per capita. So, the fundamental issue seems to be that in the US you have a larger difference between the higher and lower incomes compared to other Western nations. Count Iblis (talk) 17:55, 17 June 2015 (UTC)

Mean tropical year

The Gregorian calendar's 97 leap years per 400 year cycle yields an average of 365.2425 days per year and comes close to matching the mean tropical year of 365.24219 days. Summer solstice#External links includes Table of dates/times from 1600-2400, and looking at 400 year intervals:

1600 Jun 21 Wed at 09:51:34 UTC

2000 Jun 21 Wed at 01:48:47 UTC

2400 Jun 20 Tue at 17:11:01 UTC

suggests that we are slipping about 8 hours per cycle, or 1 day every 1200 years. From this I would conclude that we are applying one leap year too many every 1200 years, and that 365.2417 days/year (365.2425 - 1/1200) would much more closely match the tropical year, but I seem to be off by a factor of two and a half. What am I doing wrong? -- ToE 14:47, 17 June 2015 (UTC) Prompted by WP:RDMA#What are the odds of summer starting on a Sunday?

The answer is in the table in Tropical_year#Mean_time_interval_between_equinoxes with explanation just before that section. The link you used computes the time between Northern solstices, which is a little shorter than the time between northward equinoxes (which defines or at least is close to the mean tropical year). --Wrongfilter (talk) 15:25, 17 June 2015 (UTC)

Ah! So it is. Thank you. -- ToE 15:56, 17 June 2015 (UTC)

See the plan to eliminate all these discrepancies immediately above Talk:Tropical year#Standard method of verification. 5.150.92.20 (talk) 19:35, 17 June 2015 (UTC)

Slicing a malt loaf

Can anyone recommend a good technique for slicing malt loaf? They tend to get very squashed towards the end. DuncanHill (talk) 15:47, 17 June 2015 (UTC)

I use a serrated knife and saw through it slowly using very little pressure. If there's a better way I'd like to hear it too.--Shantavira|^{feed me} 15:51, 17 June 2015 (UTC)

I'd try something like Cheese_knife#Cheese_cutter, or something like this [1]. You can easily test with a simple thin wire before getting a special tool. SemanticMantis (talk) 19:14, 17 June 2015 (UTC)

Try a good ceramic knife. I use only ceramic knives to cut bread, they are not serrated and make almost no crumbs with a very clean smooth cut that does not squash the bread. If you are in the US Harbor Freight sells some very good, and inexpensive, ones. Ariel. (talk) 19:53, 17 June 2015 (UTC)

Thank you all for the suggestions. Crumbs are not an issue with a malt loaf, it's the gooey consistency. A cheesewire is worth trying, but I suspect a serrated blade with very little pressure is the most likely of the current suggestions. I shall experiment upon my next malt loaf (it was the last couple of slices of my most recent one that inspired me to ask). I'm not in the USA - do you have malt loaves there? They have always struck me as very British. DuncanHill (talk) 21:18, 17 June 2015 (UTC)

In the US we have similar things. There's raisin bread, or for something a bit denser there is banana nut bread, date nut bread and the dreaded fruitcake (said to be regifted each year at Christmas because nobody wants to actually eat it). StuRat (talk) 21:25, 17 June 2015 (UTC)

Malt loaf is a lot more malleable than fruit cake - it's difficult to describe exactly. Alansplodge (talk) 22:19, 17 June 2015 (UTC)

Malleable is le mot juste. DuncanHill (talk) 22:29, 17 June 2015 (UTC)

Hmmm, it seems Soreen, who probably know more about malt loaves than just about everyone else, use an ultrasonic system, which may be a little beyond my immediate budget. DuncanHill (talk) 21:23, 17 June 2015 (UTC)

As far as slicing the bread without crushing it, sawing the bread against a stationary blade instead of the blade into the stationary bread might help, although this also sound dangerous, and may require two people. StuRat (talk) 21:28, 17 June 2015 (UTC)

Its the gooey consistency that courses the problem. It sticks to the knife so that the next stroke drags. Medias could probably help here, as what I can remember from the old days (when people made their own malt loaf instead of buying it from the supermarket) is that they first spread it with butter. Perhaps this was to lubricate the knife and stop the gooey stuff from sticking. A couple of hours in the fridge might also help with home made maltloaf but to my mind that's close to sacrilege. --Aspro (talk) 21:53, 17 June 2015 (UTC)

Pulling the two sides apart, as a 2nd person cuts, might help there. StuRat (talk) 22:17, 17 June 2015 (UTC)

It is available through Amazon and we can learn about it here. Bus stop (talk) 23:16, 17 June 2015 (UTC)

I would never have expected that listening to a German being baffled by a malt loaf could be so entertaining. Many thanks @Bus stop:. DuncanHill (talk) 23:43, 17 June 2015 (UTC)

While I can't speak from personal experience, I have been informed that dipping the knife in very hot water between each slice helps: conversely, freezing the malt loaf and slicing while frozen also helps. --TammyMoet (talk) 12:07, 18 June 2015 (UTC)

Can we survive without oxygen for a while by injecting ourselves with D-Ribose?

Suppose that a plane suffers decompression and the plane does not descent then the oxygen will run out, killing the passengers. But since the body only uses oxygen to make D-Ribose, I was wondering if you could inject yourself with D-Ribose to survive hypoxic conditions. Count Iblis (talk) 17:28, 17 June 2015 (UTC)

• It seems unlikely, since what's essential for aerobic respiration is the production of ATP by the Mitochondria within cells using oxygen (Krebs Cycle). Injecting a sugar into the blood still requires that the sugar be transported to the heart and brain and be absorbed by the cells. Sugars themselves don't provide energy alone, they have to be broken down using O2 to form CO2 and water. μηδείς (talk) 18:39, 17 June 2015 (UTC)

There are many oxygen-consuming enzymes in the body, but I'd say one of the most important is cytochrome c oxidase, which sets at the end of the process of oxidative phosphorylation, a chain of reactions that consumes the NADH + H⁺ (removing H2 to generate NAD+) produced by the Krebs cycle to turn oxygen to water. So it is very hard to picture making up for that with ribose. But xenon has protective activity that can reduce the impact of hypoxia (see the article) Wnt (talk) 19:45, 17 June 2015 (UTC)

• These experiments with H2S are also interesting: Suspended_animation#Chemically_induced. μηδείς (talk) 03:08, 18 June 2015 (UTC)

The thing that prevents descent is unconscious pilots. Time of useful consciousness is altitude related. It's not something like "How long can you hold your breath at sea level?" At jetliner altitudes consciousness is in seconds after decompression and pilots have quick-donning masks that they train with. If it's not on in seconds, they are unconscious (your lungs can't support the pressure difference and they deflate - Scuba divers exhale on the ascent for the same reason). I don't see how an injection is faster than a positive pressure mask. Virtually all aircraft could descend to a safe altitude prior to death, though, if there is someone that commands a descent. Passenger aircraft type ratings for altitude have limits based on how long passengers will be exposed to various altitudes in the even of explosive decompression (many have a limit of FL400 because the standard is that in the even of explosive decompression, the cabin can't ever reach FL400 pressure and no aircraft can guarantee that). More insidious is a gradual hypoxia which causes confusion at lower altitudes but if it causes enough confusion about whether masks are necessary or descent is necessary, it's likely that "injection" will also be missed. Gradual decompression induced hypoxia as well as aircraft without compensated cabins all have hypoxia related confusion and fatalities. --DHeyward (talk) 22:45, 18 June 2015 (UTC)

Energy question

If energy can only be converted, never created nor destroyed, does that mean the universe has always existed? Or did the laws of physics not apply at the beginning? — Preceding unsigned comment added by 190.73.155.15 (talk) 19:57, 17 June 2015 (UTC)

Read Big Bang for some theories. ←Baseball Bugs ^{What's up, Doc?} carrots→ 20:02, 17 June 2015 (UTC)

(edit conflict) Our article on the Planck epoch discusses the limits of current scientific understanding and how well the laws of physics (as they apply now) might have been different. But for the record, it's a noticeable over-simplification to say "energy can only be converted..." even in our current physics models (it's convertible to/from mass, for example). DMacks (talk) 20:05, 17 June 2015 (UTC)

E=mc² says that matter can (under extreme circumstances) be converted to energy - and vice-versa. Since stars are rather good at doing that, instead of talking about "conservation of energy" - you really need to talk about "conservation of mass/energy". However, with that small adjustment, your question is valid and interesting. SteveBaker (talk) 20:12, 17 June 2015 (UTC)

What's a case where energy is converted into matter ? StuRat (talk) 12:44, 20 June 2015 (UTC)

Just to correct something you said there, because it is a common mistake, and I generally note that you usually don't make mistakes like this, is that mass is convertable to energy (or rather the two represent different aspects of the same property). Mass (and energy) are properties of matter, the sciency word for "stuff". When you say that matter can be converted to energy, you imply that energy is a different kind of stuff. It isn't. Energy is a property of that matter (or more properly it's a property of the universe, since energy can exist outside of matter proper). It isn't a type of stuff, it's a property of that stuff, like charge or angular momentum. We need to be careful and choose the correct words, energy and mass are equivalent, not energy and matter. --Jayron32 14:21, 19 June 2015 (UTC)

We have an article on the Zero-energy universe, though I'm not sure how this theory is currently received. -- ToE 22:38, 17 June 2015 (UTC)

The laws of physics always apply. We just don't know all the laws yet :). --DHeyward (talk) 12:34, 20 June 2015 (UTC)

Recharging cellphone from waste radio energy.

My gut feel is that the claim to extend the battery life of a cellphone by 30% by capturing waste radio-frequency energy and using it to recharge the battery is exceedingly dubious. But I can't seem to get the numbers to be sure either way.

• https://www.kickstarter.com/projects/nikolalabs/nikola-phone-case-power-your-phone-with-wasted-ene

Questions:

• What amount of battery power is typically used to drive the various radio transmitters in a cellphone?
• What fraction of THAT actually emerges as electromagnetic wave energy?
• What fraction of THAT can sensibly be captured without diminishing the frequencies needed in cell towers and WiFi receivers?
• What fraction of THAT can reasonably be converted into a 5 volt charging current?
• With what efficiency are the batteries going to be recharged? (I know they get hot while charging).

My gut feel is that when you multiply all of those together, you're not going to get anything remotely like 30% savings. But I'm finding it tough to get hard numbers for any of those things. I know that the battery capacity of one of the phones they are making these claims for has a 2550 mAh battery.

The manufacturer claims that 80% of the phone's energy is used in powering the radio...that alone seems very dubious - my phone reports 78% of the battery power being used to drive the screen alone...but I'm not typical.

I don't need all of those numbers - just enough to convince me that this is remotely plausible - or perhaps to debunk what seems like a very dubious claim.

SteveBaker (talk) 20:09, 17 June 2015 (UTC)

I did this. I used a 12x12 array of cell phone antennas. I tried parallel, serial, and grid connections. While I could get enough voltage to indicate that I had a signal (the grid connection layout gave the highest voltage), there was not enough amperage to trigger the phone to go into charge mode. Now, the first question... Did I mess things up by using more than one antenna? Using one antenna doesn't provide enough electron movement to do anything. So, I tried to use a lot of them. What I found was that no matter how you do it, when you have a lot of antennas close to one another, none of them perform as well as they did when they were alone. However, by using 144 antennas, I could get a stronger "signal". Next question... What if I use a more powerful antenna? Because I had this all set up, I used a roof-mount UHF/VHF antenna. It was no better. I used a 25-foot whip antenna. No luck. I tried to use a radar to ensure that my rig worked - they produce a lot of electron movement when receiving radar signals. My phone did blink into charge a couple times, but it was just a quick blink in and out. Therefore, from my experiment, I found that this will not work: Get some sort of antenna array and connect the live wire into a phone's charger port. Avoiding discussion of voltage/amperage/wattage... there simply aren't enough electrons moving along the wire to trigger the charge mode for the phone. But, I didn't give up there...

My next experiment is still ongoing... I found from my experiment with the roof-mount antenna that there was a distinct difference between ground on the ground and ground on the roof. How high can I get an antenna? My biggest experiment on this has been to get a large helium balloon with a 3' whip antenna dangling below it. The "string" is actually a thin shielded wire. I measure voltage across the balloon line and a ground stake and compare to voltage across a 3' whip antenna laying on a plastic chair and a group stake. I have found that there is almost always a distinct voltage difference (almost no amperage). However, wires are heavy and I can't get the balloon very high. I want to use a much larger balloon to try and get much higher - but the higher it gets, the riskier it gets. If I were to accidentally induce a lightning strike, it could be deadly. But, why does this relate? I'm doing pretty much the same thing. I'm trying to pull electrons out of the air and put them to use. Or - if you prefer - I have a lot of electrons in the ground and I'm trying to fill electron holes in the drifting air. Either way, it simply isn't very effective because the radio (be it TV, radio, phone, etc) waves are designed to be somewhat efficient. I've also been told that the reason I see diminishing returns is that, regardless of if you see it as catching or releasing electrons, all of the antenna are trying to work in the same area. It is like putting 100 fishermen on a lake and expecting to catch 100x as many fish as using 1 fisherman.

I strongly suggest that you repeat my experiment and state how it works. Most people either say "won't work" and don't try or they say "it works but there's some sort of government conspiracy" and don't try. 209.149.113.240 (talk) 20:32, 17 June 2015 (UTC)

I also doubt these claims, but even if their claims are completely accurate, I don't understand how this is even viable? The case costs $99 and gives you 30% better battery life? Am I missing something? Because that's rubbish, for a quarter of that price you can just get a phone case with a second battery in it, you can double or even triple your battery life. Vespine (talk) 23:27, 17 June 2015 (UTC)

See Wireless power for our article on the subject. Tevildo (talk) 23:44, 17 June 2015 (UTC)

You don't neccessarily need to generate enough power to trigger the charging cycle of the phone. You could use an intermediate battery which can charge at a lower voltage/current, charge that with the radio capture, and then once it's full, use it to charge the phone. Of course, that adds another source of inefficiency. MChesterMC (talk) 08:06, 18 June 2015 (UTC)

Energy harvesting and Rectenna are relevant. --Mark viking (talk) 00:18, 18 June 2015 (UTC)

Interestingly, this thing appears to be a net loss even if it's perfectly efficient. If the case attenuates the signal to a(Ω) (0 < a ≤ 1) in the direction Ω, and the antenna power output without the case is P₀, it has to put out P₀/a(Ω_tower) with the case to get an equivalent signal. The case absorbs (1−∫a) of that (omitting the normalization factor on the integrals), and if it's perfectly efficient, the overall battery drain is P₀ ∫a / a(Ω_tower). If the phone's orientation is independently uniformly random then the average battery drain is P₀ ∫a ∫(1/a). But for any a > 0, ∫a ∫(1/a) ≥ 1, with the equality being attained only when a is constant. So if the case is perfectly efficient and "omnidirectional" then it's a wash, and in every other case it makes the phone less efficient.

The most dubious assumption in that argument is that the phone's orientation is random. In reality it's probably pressed against your ear and the line to the cell tower is more likely to have some inclinations than others; you can't rule out the possibility of saving power on average by blocking less likely directions. However there's the meta-argument that if such savings were possible, phone manufacturers would design it into the antenna, since they have a huge financial incentive to improve battery life and could presumably save far more power with a better antenna than this circuitous kluge. -- BenRG (talk) 01:47, 18 June 2015 (UTC)

I don't think it makes sense for it to attenuate the frequencies that the cellphone is using to talk to the cell tower - because if the tower gets an inadequate signal, it'll tell the phone to push more power into its' transmitter. Since the transmitter isn't 100% efficient, that has to cost more energy than you can harvest.

So if this thing can work - it would have to be absorbing frequencies that are produced inadvertently outside of the 'useful band'.

Does that make sense? SteveBaker (talk) 02:10, 18 June 2015 (UTC)

From the site it self: The maximum mW output of this device is 36mW for a typical duration of 56 milliseconds on the WiFi connection during active downloading. It is a pulse charge that repeats roughly every 120 milliseconds. I could be off here but, 56ms every 120ms is roughly 50% charging cycle, so that's an average of 18mW? at 3.7v, that's roughly 5mA? Am I right so far? so to charge 30% of a 2000mAh battery, would take 120 hours? Please tell me I've made a mistake somewhere.. Vespine (talk) 06:07, 18 June 2015 (UTC)

Yes...and that assumes that you'd be doing "active downloading" all the time you're using your phone. SteveBaker (talk) 16:14, 18 June 2015 (UTC)

Wired magazine took a pretty dim view of this recently: [2] shoy (reactions) 13:58, 18 June 2015 (UTC)

Yes - but this is a bit different. They aren't talking about picking up energy from remote radio transmitters - they're collecting "waste" radio energy emitted by the phone itself. The thing harvesting the power in this product is the case of the cellphone. So the distance to the transmitter is just a few millimeters and not a meter or more as Wired assume - and the case covers more than half of the surface area around the phone, so it can (in principle) capture half of the transmitted energy. Wired is concerned about the inverse-square law here. So while I have concerns - that isn't one of them. SteveBaker (talk) 16:14, 18 June 2015 (UTC)

So, you have a phone that has a transmitter on it. You place a device to absorb the radiation right next to the transmitter (in a silly perpetual energy machine style). My first question is: How does this affect the transmitter? Will my phone lose contact with the tower? Will it reduce my wifi strength? I wouldn't be interested in extending battery life if my phone became rather useless. 199.15.144.250 (talk) 13:56, 19 June 2015 (UTC)

Head transplants and souls

lets say then that a head is cut from the body, he lose conciousness but he doesn't die as brain dead takes several minutes. during those minutes his head is put inside another body, now he has blood again. is the head now alive, or only "alive" in the scientific sense but his soul is gone? 20:11, 17 June 2015 (UTC) — Preceding unsigned comment added by 5.56.12.10 (talk)

You cannot legitimately mix discussions of science and soul. The soul is part of a belief system, not part of science. 209.149.113.240 (talk) 20:16, 17 June 2015 (UTC)

Science doesn't admit the existence of "souls" - so we can say that this question doesn't make much "scientific sense". There wasn't such a thing as a 'soul' to start with, and there won't be one at the end.

We have a really good article about Head transplants that explains that this has in fact been done with dogs, monkeys and rats with varying degrees of success - so it's more than just a theoretical possibility.

Doing a human head transplant seems quite do-able...ethical considerations and general 'weirdness' aside. As far as we know, if the operation can be done without causing significant brain damage, the patient who'se head was transplanted would awake and pretty much feel to be themselves...but severing the spinal cord would result in a total loss of feeling or movement below the neck - so this isn't such a great outcome. An Italian Neurosurgeon claims that he'll be performing the procedure sometime in the next two years - so we may not have to wait too long to find out. SteveBaker (talk) 20:21, 17 June 2015 (UTC)

Here's some news about that guy who says he can/will do it, along with some critical commentary from another surgeon [3]. Of note, that monkey only lived 10 days after the procedure. SemanticMantis (talk) 21:06, 17 June 2015 (UTC)

I hope it doesn't end like hand transplants. Majority of hand recipients choose amputation of the strange hand attached to their body. --DHeyward (talk) 05:01, 18 June 2015 (UTC)

Supposing it could be done successfully, with full functionality of the new body, forget the "soul" stuff and restrict the discussion to the consciousness of the person. You can replace any number of internal organs, and it's still the same person, albeit with some adjustments needed by that person. I don't see why a complete below-the-neck "transplant" wouldn't be the same. But there could be major psychological issues to deal with, as it could be exponentially more traumatic than the situation described by DHeyward just above. ←Baseball Bugs ^{What's up, Doc?} carrots→ 08:49, 18 June 2015 (UTC)

Well, expanding further on this tact, while consciousness and emotion are broadly seen as the product of the brain (which surely is the most essential component), they are also significantly influenced by many physiological factor that originate in the broader body, so, even controlling for the psychological toll of such a procedure and adjusting to a new body, I don't think it's accurate to say you could ever end up with someone who was entirely the same person. Their temperament and behaviour would surely by influenced, as surely as a person who has a huge fluctuation in body mass, or one who undergoes hormone therapy, or any other of a number of analogous situations which do not employ the radical circumstances of a full cephalic transplant but do entail a great deal of change in biofeedback between the head and the rest of one's physiology. Snow ^{let's rap} 22:42, 18 June 2015 (UTC)

Bleeding head good, healed head bad.[4] Short Brigade Harvester Boris (talk) 03:29, 19 June 2015 (UTC)

June 18

hair loss breakthrough

Can I know whether the research as described in this article http://www.mirror.co.uk/news/technology-science/science/cure-baldness-hopes-raised-scientists-2476939 still going on ? Can you please tell me about the progress if you don't mind ? It looks awesome and revolutionary! — Preceding unsigned comment added by 54.240.197.233 (talk) 06:54, 18 June 2015 (UTC)

Consider the source. ←Baseball Bugs ^{What's up, Doc?} carrots→ 08:44, 18 June 2015 (UTC)

It's basically still a hair transplant, just where they clone the hair follicles before they transplant them. As such, it sounds quite expensive and inconvenient. So, it might be technically feasible but still fail to catch on due to these reasons. StuRat (talk) 12:58, 18 June 2015 (UTC)

Ignoring the last two answers which don't address your question, you can find out more about it here and here. As there don't seem to have been any updates since 2013 I would assume that there is nothing further to report yet. Richerman (talk) 13:17, 18 June 2015 (UTC)

Mothballs as a "preservative" for books

Is naphthalene a good idea for protecting valuable books being stored for a few years? I have several valuable books that I need to put away for a few years - due to lack of space in my current home for a suitable bookshelf. If I wrap the books in plastic (polyethylene) with a few mothballs in the package, would they be safe? If naphthalene is harmful to paper what is a better, but still easily obtainable, alternative? Roger (Dodger67) (talk) 09:32, 18 June 2015 (UTC)

I'm not so sure that (1) naphthalene would fend off bookworms; or that (2) storing a flammable material with paper would be a good idea. You might want to contact a local library or historical society and see if they have any good recommendations. ←Baseball Bugs ^{What's up, Doc?} carrots→ 09:38, 18 June 2015 (UTC)

Forget naphthalene, it is only a fumigant insecticide. Wikipedia (as always) has an article that may help. Environmental controls.--Aspro (talk) 11:45, 18 June 2015 (UTC)

The Library of Congress FAQ page may help. DuncanHill (talk) 11:53, 18 June 2015 (UTC)

I'd also be worried about moisture, so suggest you add a chemical desiccant packet to the bag. StuRat (talk) 12:54, 18 June 2015 (UTC)

I would be cautious about desiccants - books are damaged by dryth as well as dampth. DuncanHill (talk) 17:23, 18 June 2015 (UTC)

dogs recognizing dogs

How does one breed of dog (let us say a small dog, still knows that a large dog (let us say a great dane) is still a dog. They do not look alike, but still they act agressively and smeel the other as if they still know the other is a dog????

11:54, 18 June 2015 (UTC)200.42.22.13 (talk)

You provided your own answer: smell. Dbfirs 12:14, 18 June 2015 (UTC)

Dogs determine each others' sex, age, health, reproductive status and social rank with just a sniff or two. Roger (Dodger67) (talk) 12:51, 18 June 2015 (UTC)

This question assumes that dogs do not assume that all animals are dogs. For all we know, dogs could see humans as weird dogs that walk around on two legs exactly like a dog should not do. 199.15.144.250 (talk) 13:52, 18 June 2015 (UTC)

Wolves need to be able to tell whether animals are prey animals, other wolves, or animals in some other category. Humans don't smell like wolves. Dogs do smell like wolves because they are wolves. The suggestion that dogs or other wolves don't know differences in species is silly. Wolves wouldn't have been successful in evolution if they couldn't recognize their own and others, and humans, in breeding wolves to be dogs, didn't breed species identification out. They did breed in certain attitudes toward humans, so that dogs can treat a human as alpha, but the dog never thinks that the human is an alpha dog. Robert McClenon (talk) 14:05, 18 June 2015 (UTC)

This is not a well-resolved issue, but there is increasing support for the notion that humans did not breed wolves to be dogs. Rather, the dogs domesticated themselves. See Origin_of_the_domestic_dog#Self_domestication. The notion that humans intentionally used artificial selection and selective breeding to domesticate the canine is not entirely untenable, but it seems to be rapidly loosing favor. We may never know for sure, but I've done a lot of reading on the subject, and find the self-domestication theory far more compelling. SemanticMantis (talk) 16:00, 18 June 2015 (UTC)

If the domestication of wolves was self-domestication, or was primarily self-domestication, there is still no reason to think that dogs don't know the difference between wolves and humans. Humans certainly have not "dumbed down" dogs in the selective breeding of particular breeds. Dogs, like horses, and unlike meat animals, are bred among other things for intelligence, and not knowing the difference between a wolf and a human is not intelligent, regardless of whether you are a wolf or a human. Robert McClenon (talk) 16:16, 18 June 2015 (UTC)

Sure, I was just pointing out some interesting related info on the origin of dogs. And whatever happened in the distant past, selective breeding by humans has certainly been a very strong influence in the past ~1k years. SemanticMantis (talk) 16:43, 18 June 2015 (UTC)

For some references, see Dog#Senses, Dog_behavior#Social_behavior, and Dog communication. What you are asking about is intra-species recognition, and it is very common in the animal kingdom. Even many plants can discriminate their own species from other plant neighbors and some can even tell whether a conspecific is closely related or more distant [5]. Even If you want some scholarly sources, check out this [6] which describes how dogs can not only tell that animal is a dog, but also have strong abilities in kin recognition. Here [7] is a paper that discusses how dogs can even use smell to distinguish between human twins in some cases. I'm having a hard time finding explicit evidence that dogs perform intra-species recognition (probably too obvious to merit a study), but it is a necessary pre-condition for kin recognition, and there are numerous scientific reports of that. SemanticMantis (talk) 16:00, 18 June 2015 (UTC)

It's hard to comprehend just how much information a dog gets through it's sense of smell. Some estimates say that their noses are a million times more sensitive than ours. The gulf between what we imagine can be conveyed that way, and what they must actually be able to detect is simply astounding. Dogs have been trained to detect certain kinds of cancer in humans, to pick up the scent of drugs that are triple-wrapped in plastic inside a metal suitcase, to track the scent of sweat from day-old footprints from one specific human (and no other), wearing socks and shoes, in a forest full of confusing smells of all kinds.

To try to comprehend the difference this sensitivity might make, our eyes are capable of seeing a few million colored spots at once - but suppose you could only see one color at a time - the average color of everything in your field of view - it would be like detecting bright light with your eyelids closed. Well, the difference between a million-times-more-sensitive dog nose and ours is comparable to the difference between seeing with our eyes wide open and with them closed.

Telling whether another animal is a dog or not is childs-play (well 'puppy-play') compared to all of the extreme tricks that dogs can do with their noses!

SteveBaker (talk) 16:00, 18 June 2015 (UTC)

Anyone who has walked a dog should have noticed that they're quite capable of discriminating between dogs and various other size-overlapping species instantly, by sight, at ranges of tens of yards/metres when smell is clearly not a factor. For example: walks round corner, sees a small dog some distance away, exhibits usual con-specific doggy interest via body language and voice; walks round corner, sees a cat some distance away, takes off like a rocket nearly pulling walker off feet. {The poster formerly known as 87.81.230.195} 212.95.237.92 (talk) 16:30, 18 June 2015 (UTC)

How do you know they are doing it by sight? Dogs have rather poor vision (at least by our standards) - and it's very possible that this is scent. Dogs have really good directional sense of smell too, they can determine direction from the tiniest differences in smell concentration in one nostril versus the other. Interestingly, this is slightly true of humans too (See http://www.nature.com/neuro/journal/v10/n1/abs/nn1819.html). SteveBaker (talk) 18:05, 18 June 2015 (UTC)

Well, under some circumstances, it may well be difficult to determine which element of the sensorium is triggered first, but to be fair here, no matter how much more sensitive a dog's nose is (and these "millions of times stronger" notions are massive oversimplifications that make their way into popular discussions of the topic but which don't really accurately represent the nuances of the physiology and perception involved), a scent is always going to travel at a rate that is immensely slower than that of photonic/visual stimuli. And most dogs do in fact posses visual acuity that is more than capable of allowing them to recognize prey/playthings at a considerable distance. It's color-depth (and a few other sublteties to vision which we take for granted) where their vision can be said to be less acute than ours, on the average. It's hardly full-proof, but the best way to try to make an educated guess as to whether a particular dog perceives another creature in a particular instance through a particular sense is to observe their body language. A dog catching a scent will generally keep its head low to the ground and will often keep it there for a moment, taking in the scent, before looking up and scanning on a horizontal plane, if it looks up at all. A dog seeing another animal will typically freeze in place for a moment, its vision locked on said creature. A dog hearing another creature will cock its head and attempt to position its ears (through the position of the head or the positions of the ear itself, to the degree that they have lobes capable of independent movement), to better ascertain the exact position from which the sound is emanating. Regardless of which sense alerts the dog to the animal first, as soon as it has visual attnetiveness for the creature, this sense takes priority in directing its focus, since it provides the best real-time sensory understanding. This is why most mammals, dogs included, and many other animals have a huge portion of their brain devoted to visual cognition. Snow ^{let's rap} 03:04, 19 June 2015 (UTC)

Yes, visual recognition is more important in dogs than in wolves (though both have good eyesight). Experiments have been done to determine which sense predominates, and it is sight in dogs, but smell in wolves. The difference is explained by the fact that a young puppy will open its eyes a week or two earlier than a young wolf cub. Nevertheless, if a dog sees an unfamiliar breed, I suspect that it still uses its sense of smell to determine that the strange-looking creature is indeed dog and not some other species. Dbfirs 07:22, 19 June 2015 (UTC)

DIY small-scale deacidification of books?

Is it feasible to neutralize the acid in the paper of (cheaply manufactured) paperback books, on a small scale, as a do-it-yourself project? If it is, how do you do it? --173.49.9.102 (talk) 12:29, 18 June 2015 (UTC)

I'd think alkaline fumes, like bleach fumes, might work. The two issues would be spreading the pages apart so the fumes could get to every page and sealing off the area so the bleach fumes don't damage the lungs of those in the area. Liquid bleach wouldn't be a good idea, because that's mostly water and all that moisture wouldn't be good for the book. Bleach tablets might work, although I don't know if you would get enough fumes from those. Perhaps breaking them up into powder to increase the surface area might help. Don't know if this has ever been done, though. StuRat (talk) 12:49, 18 June 2015 (UTC)

Bleach is not alkaline. Sodium hypochlorite has a pH of 7 and chlorine radicals readily form acids when binding with many other substances, so bleach would actually be counterproductive. Roger (Dodger67) (talk) 12:56, 18 June 2015 (UTC)

Chlorine bleach is highly alkaline: [8]. Ammonia is another option, although again if it's diluted with water that moisture may be bad for the books. StuRat (talk) 13:02, 18 June 2015 (UTC)

LOL. Do note that Wikipedia pages carry a formal disclaimer that they are not advice, and so if you try StuRat's off the top of his head approach to "mass deacidification" and find your comics ... bleached, well, none of us assume any liability for that whatsoever. :) (I note from that article that the approach has its risks, even when done in a serious way) Wnt (talk) 15:49, 18 June 2015 (UTC)

I was surprised that StuRat even considered bleach fumes, considering how corrosive bleach is. I actually considered ammonia (gas) before I posted the question. What I couldn't tell was whether it would be effective, whether the effectiveness would last, and whether it would cause other problems for the books being preserved. A small amount of ammonia is quite easy to generate. It is released by warming household ammonia. Confining it and recapturing unreacted ammonia seem relatively easy too. Does anyone know whether it will work, as a question of chemistry?

Another idea that I considered was dilute solution of antacid. I've seen it suggested for preserving newspaper. I have concern about the effect of water on bound paperback books. --173.49.9.102 (talk) 14:19, 20 June 2015 (UTC)

The reason bleach is so corrosive is it's alkalinity. If you use too much, then yes, this would be a concern. A small amount, however. should be completely neutralized by the acid in the paper, same as ammonia. Of course, getting this balance just right could indeed be tricky. I'd start with some practice books I didn't care about. Same applies to ammonia. You should be able to test the book's pH before and after with litmus paper (although you would have to wet the sample with some distilled water, another reason to use books you don't care about). StuRat (talk) 14:37, 20 June 2015 (UTC)

(ECs) Serious Comic book collectors store their volumes in individual bags made of special plastic, which in turn are kept in boxes made of special cardboard to minimize acidification, and may interleave the pages with sheets of special de-acidifying paper. Also, libraries have batches of books treated by exposure to de-acidifying gases in chambers made for the purpose, run by commercial organisations (see our article Mass deacidification). Presumably the latter process could be recreated as a home project, but I suspect it wouldn't be trivial. See also our article Conservation and restoration of books, manuscripts, documents and ephemera for possible links to useful information. I really ought to look into it myself, having a personal collection of fiction and non-fiction amounting to an estimated 18,000 volumes :-). {The poster formerly known as 87.81.230.195) 212.95.237.92 (talk) 13:11, 18 June 2015 (UTC)

Have you had a look at Preservation (library and archival science) and in particular mass deacidification? I think you really need to have a buffer deposited rather than expose them to a reactive gas which will probably cause other damage. Nearly all cheap paperbacks and even many books from more than thirty years ago are liable to go brown and brittle very rapidly. Dmcq (talk) 13:29, 18 June 2015 (UTC)

1 2 Agent of the nine (talk) 15:13, 18 June 2015 (UTC)

I've come across mass deacidification processes during my search for a solution, and that's the reason I asked about small-scale deacidification specifically. Any more suggestions? --173.49.9.102 (talk) 14:19, 20 June 2015 (UTC)

Hm. I think it may be over hopeful to expect NASA or the National Bureau of Standards to help in the DIY project even if they were very helpful with the Declaration of Independence. :-) Dmcq (talk) 17:19, 18 June 2015 (UTC)

• You might do well to contact a business like Talas that provides book preservation supplies or a bookbinder of which there are many, for example, in NYC who can advise you on the feasibility and cost of such a project. You can do the same sort of google search for Philly if that's easier, but I would call Talas first. μηδείς (talk) 21:46, 20 June 2015 (UTC)

Bearings are sticky - is this normal or has oil degraded?

I bought some of these bearings two years ago and am only ready to use one of them now. I took one from the wrapping and they're covered in something sticky. Further, the bearing rotates but it doesn't rotate freely - it feels like the sticky stuff is on the inside. Is this because the oil has degraded or are they meant to be like that? --78.148.104.139 (talk) 14:46, 18 June 2015 (UTC)

I'd certainly expect these kinds of bearings to spin freely and to not require additional lubricants or anything like that. I use these kinds of bearing in my laser cutters - and I've had spare parts sitting around in my workshop for more than 2 years that worked just fine when I came around to using them.

I suppose it's remotely possible that they were packed in some kind of anti-corrosion grease that you're supposed to remove before use. I'm thinking of something like Cosmoline (except that's unlikely to be the stuff they used unless these are ex-military parts). Oil put into the bearing as a lubricant ought to have been protected by the rubber seals - if they are still airtight. The ones I have don't require me to add or change lubricant - they are sealed for life - so they shouldn't get sticky. I suppose that if you've stored them in some place where there are extremes of temperature, the rubber seals may have degraded and somehow leached some kind of sticky material onto the bearing surfaces.

The trouble with this kind of vendor on eBay is that you generally don't know where they bought their stock from - and it could be factory surplus or something...these bearings might have been sitting on a shelf for decades before you got them.

With open bearings, you could probably soak them in some kind of solvent to dissolve away whatever this goop is - and then re-lubricate them with some light machine oil. But these bearings are supposed to be rubber sealed - and if the seals are working, the solvent won't get into the bearings. You'd also be likely to wreck the seals (if they aren't already wrecked), which would 100% guarantee that you'd have problems in the future.

Sadly, that ebay seller says that their returns policy isn't going to let you return them...but you could use ebay to ask the seller a question about them.

Incidentally - one super-cheap source for these kinds of bearings (although with a limited range of sizes) is to look for them where skateboards and rollerblades are sold - if you can use the sizes they have, you'll pay a quarter of what most engineering sources will charge for the exact same thing! Here in Austin, TX we have a skateboard shop, catering to the people who like to geek-out their boards with the fastest possible wheels, trucks, bearings, etc - and they have some REALLY good bearings for very low dollar.

SteveBaker (talk) 15:49, 18 June 2015 (UTC)

Perhaps the bad design is in that they used a rubber that the oil degrades? Some rubber does go sticky if it is very old. Dmcq (talk) 17:01, 18 June 2015 (UTC)

Okay, so I cleaned the bearing in "turpentine substitute" and now it turns freely. Perhaps the rubber seal is working just fine and this stuff coating them was just for protection as suggested? Anyway, thanks; I'll bear in mind that they may not function as expected - nothing bad will happen if they don't. :) 78.148.104.139 (talk) 17:36, 18 June 2015 (UTC)

That's good, sounds like it was just some protective grease like SteveBaker said. Dmcq (talk) 20:29, 18 June 2015 (UTC)

I worked in a tool shop for a few years and I would say what you had was probably perfectly normal. Some resistance in the bearing is not abnormal, they're generally not made to spin "freely". In a tool, a little bit of resistance in the bearing is going to be nothing compared to the stress of the working bit. Some bearings are rated to many tens of thousands, even hundreds of thousands RPMs, and in that kind of application you most certainly don't want to be lubricating bearings with machine oil, that is far too thin, in that kind of application you need a sticky grease. However, if you're using the bearings just in a "guide", or a rolling application then you are probably fine even if you don't lube the bearing at all. Vespine (talk) 23:17, 18 June 2015 (UTC)

• Oh dear, this does not sound good. Tribology is a science. The manufacture probably applied the 'right' kind of grease for the application and now you have removed it. Viscosity can be important. Step-by-Step Grease Selection--Aspro (talk) 23:17, 18 June 2015 (UTC)

Note, some bearings need to be operated only when installed. An example are automotive wheel bearings. Improper mounted or not specified tightened screws cause an immediate and permanent damage to the balls inside. These bearings use not such kind of grease. These lubricated are lithium soap, MOS2 and graphite to cover a failure of the other lubricates. Some of these lubricates get thin like water when reaching 70 °C (~ 160 °F). When operating an new bearing several minutes, it is running better. --Hans Haase (有问题吗) 09:30, 21 June 2015 (UTC)

People mistaking the gender of babies

Following on that dogs recognizing dogs discussion, something I've been wondering about is that some babies seem to get an inordinate number of people thinking they are of the opposite sex - despite the girls having pink dresses with butterflies on or the boys being dressed in blue and having a train type toy. It happens for all babies that some people just say he or she without thinking but for a few it is really noticeable to the extent it annoys the mothers. Any idea what could be the signs that put out this signal and override the conventions about colors? Dmcq (talk) 16:50, 18 June 2015 (UTC)

Human infants don't really have a gender (other than the ones assumed by a community), but they do have a sex. Gender norms are learned/put upon a baby, not chosen (poor wording; choice and preference certainly comes in at some age). And we all know pink is for boys, right? Pink#The_19th_century. Anyway, Neoteny#Neotenic_traits_in_humans shows several physical ways in which (clothed) babies are sexually ambiguous. Many cultures have a notion that male is the default sex [9], our related article is at Androcentrism. SemanticMantis (talk) 17:50, 18 June 2015 (UTC)

That isn't true that Gender norms are put upon a baby, not chosen. Go ask transsexuals who believe they were born the wrong sex if that's true. Or go ask a parent if that's true. It's a commonly repeated thing, but it's utterly false. Babies most definitely do have a gender, it's just less obvious to someone who doesn't know the baby, that's all. Ariel. (talk) 18:58, 18 June 2015 (UTC)

I have to disagree with SM strongly, my niece was never coached in any way to be feminine, and she started spontaneously mimicking female TV characters, especially ballerinas, before she was two. Her parents are very progressive, and she has two older brothers, but she is radically feminine. μηδείς (talk) 19:24, 18 June 2015 (UTC)

Maybe we are having a problem with terminology. I was thinking primarily of young humans certainly under 1 year old, and probably younger. Surely most of us acquire a gender, through choice, exposure, community, etc. at some point as we grow up. There may even be a genetic or sex-influenced component. Surely most adults have a gender. But in scientific terminology, gender is primarily considered social construct, and is part of a person's personal self image - this is all explained in the article I linked above. As such, nobody under the age of 6 months (an infant), who hasn't even gotten object permanence fully sorted out, has any notion of whether they are more masculine or feminine, or who they might prefer sexually, or anything else that goes in to our concept of gender. Nothing I said contradicts the notion that some people believe they were born the "wrong" sex (gender disphoria), nor does it disallow some toddler starting to mimic female figures. Indeed, the mimicking of behaviors is one key way children learn, and that's why I put "learn" in my comment above. To my reading, both of your comments are perfectly congruent with what I wrote. You are both of course free to disagree with me and the information in our articles, but unless you can find some serious academic references that support the notion that an infant has a gender, I don't really find your complaints to be a very compelling criticism. If you want to think a 4 month old is clearly "masculine" or "feminine" because of what they seem to like, then knock yourself out, but that isn't really a scientific approach. To clarify, I think it's totally reasonable to say a 2-4 year-old child has a gender, but that's very different from claiming that a 2 month-old infant does. I was assuming the OP meant somethign closer to the latter than the former, as most people do not mistake the sex of most toddlers. SemanticMantis (talk) 22:55, 18 June 2015 (UTC)

I agree with SM. I also think it's foolish to assume parents can definitely completely avoid inadvertent gender related treatment, no matter how progressive they are. Also unless a person is living in a cult with zero outside influence, the influence of people besides the parents or general society can't be ignored, and again, it's foolish to assume there will be no gender related treatment, no matter how progressive anyone is. If someone is following TV characters, they clearly aren't in a cult with no outside influence. Nil Einne (talk) 15:43, 19 June 2015 (UTC)

Yup. Point in fact, it's a well-known observation amongst developmental psychologists that the influence of parents is not all that it is cracked up to be in popular belief -- this belief is understandable in that parents obviously want to believe they have control in shaping healthy habits and positive or desirable traits in their children, but does not really jive with the reality, when we study the outcomes of personality traits in an empirical fashion ([10], [11]). In reality not only does environment not play the overwhelming role most people intuitively expect, parents aren't even necessarily the major players in terms of the environment, as children often takes their ques more readily from their peers, or elsewhere in the voluminous amount of social influence tossed at them from all directions. Snow ^{let's rap} 21:17, 19 June 2015 (UTC)

Well, think about it - what distinguishes male from female in traditional western world settings?

• Body shape - hips, boobs, shoulders all have different dimensions in adult men and women. Not so in babies.
• Hair length & style - babies don't have much hair - certainly not enough to style.
• Clothing style - babies mostly wear the same stuff whether boys or girls - although admittedly, color choices may vary.
• Size - men are generally larger, but babies are all over the map in weight and length in their first year.
• Facial features - babies have round chubby faces - both sexes look the same.

The pink/blue color convention was a reliable guide for a while - but very often our <1yr grandkid is wearing a "What happens at Grandma's house stays at Grandma's house" t-shirt and baggy pants that cover up the inevitable diaper, and yellow and pale green seem to be popular colors with both sexes. So it's not always helpful - and babies may also be wrapped up in blankets with much of their clothing hidden anyway.

Incidentally, you might be surprised to know that as recently as the 1930's, pink was not a 'girls color' at all - it was considered decidedly masculine (See Pink#The_20th_century) - the stereotypical colors 'flipped' in an astoundingly short amount of time right around 1940! SteveBaker (talk) 17:52, 18 June 2015 (UTC)

Well yes exactly - there's very little or no difference between girl and boy babies except the clothes they wear, yet some that don't appear particularly different to me get people often saying he or she about them despite the clothes color. It isn't just them all being called he because sometimes it happens the other way round too. The latest case I'm thinking of is a little baby girl of two months and the only difference I can see is she is more active and alert than most. I don't see how people could spot that immediately if they don't notice the pink and frills or even a pretty headband with a flower design like a flapper. Dmcq (talk) 18:50, 18 June 2015 (UTC)

Like Ariel writes above; gender is not in your clothes, hairstyle, body type and whatnot. It's not in your upbringing either. It's in your head and in your heart. As a transsexual I know what I'm talking about. I was a boy even when I dressed and looked like a girl, and was brought up like a girl. Babies of course have a gender, only that they can't tell us. ... I agree though that both boys and girls LOOK the same up until a certain age. /Kristian — Preceding unsigned comment added by 176.71.52.77 (talk) 22:47, 18 June 2015 (UTC)

Yes, masculinity and femininity were widely believed to be acquired behaviours until the sorry case of David Reimer proved otherwise. Alansplodge (talk) 23:23, 18 June 2015 (UTC)

I don't think the David Reimer case really proved anything except how dangerous a botched circumcision is and what a stupid idea it was to try and force a gender role on him and to do reassignment surgery at such a young age.

For starters a single case can rarely prove anything whatever happens and this should have been (although unfortunately wasn't so much at the beginning) considered whatever the believed outcome.

More importantly, he hardly had a typical childhood with the therapy sessions, whatever the truth about what went on in them (and whatever the reason for some of them whether stuff Money didn't know about or just bad ideas on his part), parents who realisticly were unlikely to treat him anywhere like the same as they would have a girl, the natural problems that come from reassignment surgery even more so given the techniques then etc. (Note that even overcompensation could easily have been a bad thing in many ways.)

Children do sometimes have severe psychological problems while growing up including fitting in, they don't normally find out they were actually born with a penis which was destroyed by circumcision and they then had reassignment surgery and attempt was made to forcely raise them as a girl. (And to be clear, I'm not saying they shouldn't have told him, rather he should have known much sooner, without having had any reassignment so he could decide for himself what he wanted.)

Also the foolish attempt to force a gender role only happened sometime between 7-22 months.

This isn't to suggest that gender disphoria isn't real, it obviously is, but simply what I said at the beginning i.e. that we can't really learn much about the acquired vs genetic, or even acquired after birth vs acquired before birth from this case. We can perhaps say that it appears there may be a component which is present by 2 years of age or so, but even that should be treated with caution.

And just to avoid any controversy, I should be clear I'm not saying, gender is acquired (although I do think it is unlikely there isn't some component that is acquired) or that it doesn't exist, rather that it's unlikely we'll know for a long time yet and we shouldn't read too much in to the scant evidence, but instead take the best lessons to learn from the little we do know, which does appear to be closer to what Milton Diamond advocates then John Money.

Nil Einne (talk) 15:43, 19 June 2015 (UTC)

I'd say it's rather inaccurate and reflects a dubious understanding of neuropsychology to claim that babies have a gender that "they just can't communicate to us yet". They simply are not, at that stage of development, in possession of a brain and neurocircuitry capable of processing and actualizing gender roles. The human organism at that age has more or less identical needs, regardless of the biological sex, and a very simple and mostly universal array of social and communication ques with which to interact with other people, relative to a mature individual. It is also absolutely true that at this point they already have a degree of genetic determinism which will have a powerful innate influence on how they will process gender as they continue to develop and that these biological factors combine with environmental ques to determine the ultimate identity of the individual. But just because a person identifies with a gender that some see as incongruent with their biological sex (or more accurately, their external sexual phenotype) does not mean they "had that gender all along" from the point of birth or conception. It only means that its possible they were always biologically determined to incline towards that identity, and that their upbringing could only influence those traits so much against that natural inclination. For more details on this distinction, see SemanticMantis' informative post above, and the articles to which he links. Snow ^{let's rap} 00:32, 19 June 2015 (UTC)

Thanks, well put. Also worth pointing out nature vs. nurture, and that gender can be influenced by both. The sad case linked above doesn't do anything to disprove environmental factors, nor does the existence of somebody who freely chooses to change gender as an adult disprove the existence of genetic factors. Kristian's comment above is completely in line with sex not being the sole determinant of gender. The other thing that might be tripping up the conversation is there is one sense of gender that is usually completely assigned - on the day a baby is born XY with normal genitals, he is called a boy, and implicitly given a masculine gender (and vice-versa for XX/Female, at least most places in the modern western world). That is a bit different from the notion of gender that is tied up with self perception, gender performance and sexuality of adults. SemanticMantis (talk) 00:50, 19 June 2015 (UTC)

And there's further both generational and contextual divides in the factors you reference with regard to how "gender" is semantically utilized and interpreted. Before contemporary perspectives and scientific advancement began to disentangle them, "gender" was often used in a fashion where it was much more interchangeable with (biological) "sex", and in many cases in common parlance, this perception persists. It wasn't until the social and behavioural scientists of the second half of the last century started to feel a pressing need to have two terms (one which applied to social identity and one to overt physiology) that the terms started to take on their more distinct meanings, and even then it wasn't until the last decade (and the last few years in particular) that this distinction truly started to permeate into general usage, and that transition is still far from complete and the lines between the two can be tricky on occasion even for those who use it consistently in professional or deeply personal contexts. The whole situation is further complicated by the fact that, though we increasingly use these terms with a more nuanced understanding of the biological implications, the academia which first developed it's usage was rooted in rather soft and dubious social science. Specifically, some of the "radical" voices of second-wave feminism used the gender/sex dichotomy as an underpinning to their arguments that gender was a completely socially-constructed phenomena, and that, if not for entrenched culture, there would be little or no distinction between the sexes. That extreme interpretation is not taken very seriously by cognitive scientists today, but it's proven surprisingly tenacious in some outlying veins of sociological "study". This notion has had consequences for those with gender dysphoria today that few would have anticipated at the time, since many people continue to regard gender as a social construct and oppose the notion that a person might be hard-wired to tend towards a certain gender (and that this wiring might at times be inconsistent with their genitalia and secondary sexual characteristics).

There's another point you touch upon which I think warrants some discussion as well, and that's the interplay between innate/genetic tendency (I use this in place of "determinism" for reasons that I'll shortly elucidate on) and environmental influence -- that is "nature vs. nurture". For the longest time, as we all know, arguments against the acceptance of non-heteronormative sexualities and transgendered identities hinged on the notion that they were "against the natural order" and thus the question of whether LGBT persons chose (or were socially influenced towards) their preferences or whether they were genetically programmed in this regard and had no choice in the matter, became one of the central ideological battlegrounds around which their fight for acceptance and rights were conducted. But research is telling us increasingly that in the fight against the intolerant "these people just aren't natural" arguments, the opposing perspectives may have over-corrected when they began to assume that sexuality and gender were completely determined at birth, and that environment cannot make even a dent on the resulting sexuality or gender identities of a mature person. These are hot-button topics (especially with regard to transgender identities of late) and few researchers want to be amongst those who publicly talk about the notion that sexuality and gender identity may not be as firmly hard-wired as has been implied, for fear that they might be mistaken for the intolerant voices of the past. But there's an increasing tendency amongst those who research sexual orientation through the lens of biology to say that many people are born not with a set specific biological determinism to be straight or gay, but that rather they are born with "spectrum" of possible sexual identities, and that environment then fine-tunes the specifics. What's more, the identities they do "lock into" in these regards are not necessarily permanent. As global perspectives towards homosexuality change, and more people live freely and openly with their non-heterosexual decisions, interesting data is starting to emerge. There are some people who seem to move back-and-forth between being gay and straight in different periods of their life. Nor are these people exactly "bisexual" in the traditional sense -- they often report feeling exclusively attracted to one gender and then another during different periods of their lives. Further, we've observed similar tendencies in other animals species for a long time, and noted that these tendencies tend to change with the environmental factors around them (habitat, local population size and so-forth), though obviously this is not quite the same thing as the complex social expectations that partially define the sexual environment of humans.

The extent to which gender identity parallels these ambiguities is unknown; we're very much at the beginning of studying these phenomena in an empirical fashion, despite the fact that they've surely been with us since the advent of our species (and probably much, much father back into our distant ancestry). But we do know that there are a great many people who secretly identify as transgender to greatly varying degrees who never feel compelled to transition or even broadly acknowledge their "alternative" gender identity. My personal educated guess is that "gender fluid" identities (to use the new buzz terminology) are more common in the inner lives of many people than has traditionally been assumed, and certainly we see a lot of experimentation in youth, though some are shamed out of it, and others pass through it relatively quickly without any particular pressure. But bringing all of this back around to the original topic of discussion, I think (as with most every other domain of human behaviour and expression) people have artificially divided "nature and "nurture" into two distinct and competing forces, in a manner which does not jive with our more scientific understanding of the process of individual development. In truth, they are one process, not easily separated if you really want an accurate and complete story of how a person's propensities and outlooks are formed. But the separation of these processes into two schools of thought has proven useful to those who want to argue these topics from ideological perspectives, and so the debate persists in these terms of oppositional forces. But it's going to be increasingly recognized as an untenable way of characterizing human development, moving forward. Snow ^{let's rap} 02:39, 19 June 2015 (UTC)

I have no idea why people have problems with this, so I've just given up and gone with Hanlon's razor. shoy (reactions) 13:50, 19 June 2015 (UTC)

I don't think even that principle applies, since it's not a matter of stupidity to fail to pick up on gender-specific ques in the faces of male and female babies, because in reality these ques don't really exist. Snow ^{let's rap} 21:21, 19 June 2015 (UTC)

If someone sees the drawing of the Gerber baby, for example, and doesn't know anything about its history, I can't imagine how someone could know the sex of the illustrated child. ←Baseball Bugs ^{What's up, Doc?} carrots→ 06:33, 20 June 2015 (UTC)

Ambulance training

Are ambulance crews trained to deal with panic attacks? I heard that much ambulance time can be wasted dealing with them as they are not life threatening. 2001:268:D003:EA32:38E8:7ECB:6307:9367 (talk) 20:53, 18 June 2015 (UTC)

I see absolutely no reason to think the answer to your question is anything other than yes of course they are. It would not necessarily be immediately obvious if someone is suffering a panic attack or something more serious (like a heart attack) and in that situation I think the "better safe than sorry" rule applies. Just doing a quick google it seems like it's not unheard of for a panic attack to land people in hospital. Vespine (talk) 23:01, 18 June 2015 (UTC)

true but many ambulance services worldwide are campaigning for people to stop calling them in non life threatening case as it uses up resources. Surely a panic attack would fall under that. 106.142.246.1 (talk) 23:05, 18 June 2015 (UTC)

Well, I found several ambulance services that have advice on how to deal with them their websites [12] [13] - perhaps they're hoping that you will use Google instead of calling them. It has been included in every first aid course that I have attended (I've lost count though - the first was in 1976) so on that basis I believe that the answer to your question is "yes". Alansplodge (talk) 23:18, 18 June 2015 (UTC)

Really? It's never been covered on any I've attended. 106.142.246.1 (talk) 23:30, 18 June 2015 (UTC)

This is sort of an unrelated side question but any idea why when I signed my original question it gave a weird IP address? 106.142.246.1 (talk) 23:32, 18 June 2015 (UTC)

Your first posting has an IPv6 address, but your subsequent postings have IPv4 addresses. Which type of address you get is determined by your ISP and networking hardware. Tevildo (talk) 23:45, 19 June 2015 (UTC)

Well that's fine if you know for certain that someone is suffering from a panic attack. However, if I was confronted with someone suffering from symptoms such as: shortness of breath, heart palpitations or a racing heart, chest pain or discomfort, sweating, numbness or tingling sensations etc.[14] I would call an ambulance and let the professionals decide whether they were suffering from a panic attack or a heart attack. Richerman (talk) 23:32, 18 June 2015 (UTC)

Indeed, a Google search brings up several cases of heart attacks being misdiagnosed as panic attacks by paramedics or ambulance technicians, sometimes with fatal consequences. Alansplodge (talk) 01:59, 19 June 2015 (UTC)

There is no way that anyone will advise a person to call anything but 911/999 if they believe it is a medical emergency. Panic and anxiety are precursors to a number of physical ailments such as cardiac arrest. It's perfectly acceptable to treat a patient as having a heart attack even if it later turns out to be a panic attack. They will be conservative since misgiagnosing a panic attack as a heart attack is inconvenient but misdiagnosing a heart attack as a panic attack is fatal. --DHeyward (talk) 00:31, 21 June 2015 (UTC)

Ivory-bill woodpecker

Where are ivory-billed woodpeckers currently being seen? — Preceding unsigned comment added by Kcinrawm (talk • contribs) 22:01, 18 June 2015 (UTC)

Nowhere with any certainty. See Ivory-billed_woodpecker. We have no strong evidence that the bird is not extinct. There have been some unconfirmed sightings claimed (which may not be the bird at all) in 2005-2006. If there are any birds left, they are most certainly currently below the Minimum_viable_population. One place to look would be along the Choctawhatchee_River. If you can find one and lead a biologist to it, you can win a $50k prize. Sadly many experts believe it is just a matter of time before they can be officially declared extinct :-/ SemanticMantis (talk) 22:30, 18 June 2015 (UTC)

There are stuffed specimens in some museums, and that's about it. ←Baseball Bugs ^{What's up, Doc?} carrots→ 16:58, 19 June 2015 (UTC)

Impact of water pressure on a scuba diver

Can someone help me understand the impact water pressure has on human scuba divers? I'm curious and have a few questions about what happens at typical scuba underwater depths.

When a diver is underwater, does the water above a scuba diver effectively push down on the diver? If so, does that pressure act to drive the diver deeper into the water? If not, why not?

I also recall hearing that water pressure can impact the lungs and lung capacity. I believe the comment implied that the lungs essentially shrink based on the water pressure. Can someone elaborate on what impact (if any) water pressure has on a divers lungs and how that occurs? Do the lungs actually shrink, or does it have more to do with the water pressure causing a diver's chest to be compressed? 68.96.8.201 (talk) 23:26, 18 June 2015 (UTC)

The reason the diver is not pushed downwards is that the pressure acts on him/her from all directions - not just from above. There's a description of how pressure affects divers here. Richerman (talk) 23:54, 18 June 2015 (UTC)

Scuba stands for self-contained underwater breathing apparatus'. The regulator delivers air at the same pressure as the surrounding water so that the lung capacity (volume/size) remains the same as it is on the surface. Although the water above the diver has mass and density, the water below has mass and density also, and both cancel out. Therefore, the water above doesn’t force the diver deeper. A free diver (i.e. holding his breath as he dives down from the surface) will suffer reduced lung volume as he descends and will find it becoming easer to swim down as he loses the buoyancy from his shrinking lungs. --Aspro (talk) 00:05, 19 June 2015 (UTC)

It is also important to know that because SCUBA regulators deliver air at the ambient pressure, they are necessarily delivering a lot more molecules of air at depth. It gets complicated, but you use up about twice as much of your tank's content at double the depth. The practical aspect is that greater depth = less dive time, and that's even before you have to allow for slow surfacing.176.46.102.175 (talk) 02:14, 19 June 2015 (UTC)

But it's more complicated than that, because each breath at great depth brings more oxygen (and other) molecules into your lungs. So, you don't need to breathe as often! However, for safety, a diver needs to breathe regularly: this prevents pulmonary hyperinflation. Also, at great depths (high pressures), the pesky other molecules in air also get into your blood stream at a faster rate. Specifically, nitrogen enters solution in your blood and tissue, and if you are not careful, you can get the bends (the most serious problem associated with decompression sickness). Unusual gas concentrations in your blood can also cause nitrogen narcosis and oxygen toxicity. Regular divers ("SCUBA divers" in the terminology of NAUI) are usually limited by breathing gas pressure: they run out of gas after about half an hour to one hour, and it's time to come back up. The next tier of advanced divers ("Enriched Air, Nitrox Diver" in NAUI's certification scheme) may dive deeper a different dive profile, and their safety is limited by nitrogen narcosis: so, they put less nitrogen and more oxygen in their air tanks. Divers who go very deep for a long time are usually limited by having too much oxygen (not too little gas pressure)! This is why deep divers breathe trimix gas. They put less nitrogen and less oxygen in their tank, and fill the rest with helium. This mixture is not usually safe or comfortable to breathe at atmospheric pressure, so these divers may use ordinary compressed air or Nitrox to start their dive, and then switch tanks at the bottom.

The air in a skin diver's lungs does shrink: as they dive deeper, their lungs squish and become very small. A SCUBA diver is constantly equalizing the pressure in the lung using the SCUBA regulator: so the lungs should not change size significantly - that would only happen if you hold your breath, which is an unsafe diving practice that can lead to pulmonary hyperinflation. However, the rest of a diver does compress at depth. At only thirty feet, your neoprene weight belt is usually too loose because your body has physically shrunk: but if you tighten up the gear, it will crush you when you return to the surface!

SCUBA diving is complex: there is a lot of technique, safety procedure, and physiology related to pressurization (among lots of other important knowledge!) that you must learn thoroughly before you can safely dive.

Nimur (talk) 06:38, 19 June 2015 (UTC)

You may want to review nitrox diving. It extends dive times in shallower depths. It never allows deeper dives than regular air because the enriched oxygen is toxic. It only extends the time allowed at a shallower depth since the reduced nitrogen helps with the bends. Toxic partial pressures of oxygen limit dive depth, nitrogen limits dive time. Nitrox allows custom, shallow depths with maximum time since you can basically go to the oxygen partial pressure limit at the cost of depth. A nitrox chart should bottom out before compressed air. --DHeyward (talk) 08:42, 19 June 2015 (UTC)

Yikes, what I wrote earlier was not right! Thanks for correcting me. Of course, both nitrogen narcosis and oxygen toxicity will limit your dive, so your dive profile needs to be constructed within both limits. Always check your dive tables and consult your dive master. The summary DHeyward provided is more in line with the textbook answers. On the flip-side, the deepest dive I ever did was a Nitrox dive, so my mental heuristics are backward. If we were going for maximum depth in a dive profile, and were limited only by the dive depth, then compressed air would typically take you deeper than enriched air, but you'd have less time to get there and less time to get back. Nimur (talk) 12:13, 19 June 2015 (UTC)

For just buoyancy, the neoprene suit is buoyant as well as lungs above the surface (and fat). Divers wear weights to compensate but this usually doesn't change the positive net buoyancy at the surface. At a certain level below the surface (usually around 5-10 feet in my experience), the density of air in the lungs is high enough that buoyancy changes to more neutral to slightly negative. Breathing makes the diver rise and bob at the surface. This diminishes at depth so that inhaling doesn't change the divers depth like it does near the surface. I can feel the depth where inhaling no longer rises and the tendency is to sink. Neutral buoyancy is the goal so the diver is not fighting the sink or the rise. In an emergency, there is a rapid inflation device as well as a quick release of weights but that's not a recommended ascent. Beats drowning though. --DHeyward (talk) 08:29, 19 June 2015 (UTC)

Thanks everyone for responding, thats interesting info! Nimur, I'm not sure if that link to skin diver was the intended target? Also, any suggestions on where can I learn more about the lung squishing you describe? This is all just curiosity, I'm not planning on diving myself. (OP, but on a different machine)128.229.4.2 (talk) 13:30, 19 June 2015 (UTC)

Sorry, our article on the topic is freediving. I will fix my link. Nimur (talk) 14:27, 19 June 2015 (UTC)

Do window coverings have an impact on A/C usage?

I got an email at work asking employees to close the blinds on hot days - particularly when the sun is directly shining through the window - in an effort to reduce air conditioning costs. That made me wonder - does closing blinds really have a noticeable impact on an air conditioner's workload? Assuming that window coverings are just regular fabric material of a grayish color, will closing them really effectively keep more heat out of the room? Or does it just cause the window coverings themselves to absorb the sun's rays and heat up vice the entire room absorbing the sun's rays? Wouldn't the air conditioner have to do roughly equivalent work to cool down the window coverings that absorb the sun's rays as it would if the coverings were opened and the objects in the room absorbed the suns rays?

I guess my question boils down to this - does it really matter what object inside of a room gets hot by absorbing the sun's rays? Be it the window coverings, or the desk opposite the window, wont the air conditioner have to contend with either circumstance in a similar manner?

I'm sure specific conditions make a difference, but i'm just curious about any answer anyone may have in general. 68.96.8.201 (talk) 23:27, 18 June 2015 (UTC)

If the window covering reflects solar energy (instead of absorbing it), then there is less net total energy entering the room. Nimur (talk) 23:42, 18 June 2015 (UTC)

And unless your shades are made of Vantablack, you'll be reflecting some non-trivial radiation. SemanticMantis (talk) 00:24, 19 June 2015 (UTC)

As you say, specifics may have a noticeable effect on the answer to your question, particularly the qualities of the windows, the blinds, the specific temperatures and the space involved. In general, though you do raise a factor that can significantly mitigate the benefit in efficiency expected from closing the blinds, but there are properties of thermal conduction in complex systems you haven't necesarily accounted for, all the same. Consider, for example, that the blinds may absorb a great deal of heat but not release all of it into the inner-more space to have a significant impact on the processes of cooling the air therein. A great deal of the heat striking the blinds may be radiated back in the direction from which the photons emanated, traveling back through the glass or remaining for a time in the space between the glass and the blinds. Depending on the material qualities involved, a significant amount of heat might be kept isolated in such a fashion until a time of day when the building is no longer as heavily occupied (and this air conditioning is not as warranted) or until the overall heat in the complete system of both the building and its external environment drops (as night approaches, for example).

There's also another factor that doesn't so much influence the overall amount of thermal energy involved, but will still play a major role in the degree to which AC is employed. That is, in the majority of cases, AC is utilized not because the building itself needs to be kept at a particular temperature (though certainly there are many cases where this is a practical necessity) but rather more often for human well-being and comfort. In the case of the blinds being open, the light and accompanying heat can travel farther into the inner environs and heat up individuals directly. Although these people represent only a small portion of the mass involved in the total system, their particular heat is a defining factor that goes forward to exert considerable influence over how the AC is then utilized, particularly in systems that are not fully automated. And sometimes its not even so much a factor of their core temperature significantly changing as it is a matter of perception of heat. Considering all of the factors above, I'd say the answer is really "it's highly dependent upon the circumstances" (but then you clearly already realized that), but I would say there can easily be circumstances where the overall efficiency of a system could be marginally significant enough for the blinds issue to warrant the attention of someone managing a large enough space, especially if the building is not particularly well weatherized. Of course, there is also something to be said for the corresponding psychophysiological effects of decreased natural lighting on the overall efficiency of a human system, but that's another topic altogether. Snow ^{let's rap} 00:10, 19 June 2015 (UTC)

Here it says: Internal venetian blinds 55 – 85%. Even without A/C we close the binds and curtains for this very reason. Walk into a room where you haven't done so and it is noticeably hotter.--Aspro (talk) 00:23, 19 June 2015 (UTC)

Aspro, I'm not getting a working link for that URL; perhaps you should double check if this is the working address you intended to add. (Feel free to delete this post of mine when you correct the link, to save space, if you are so-inclined.) Snow ^{let's rap} 00:53, 19 June 2015 (UTC)

Thanks. The link should now work--Aspro (talk) 16:03, 19 June 2015 (UTC)

If the sunlight is turned into heat at the window, much of that heat will radiate right back out the window, and not enter the rest of the room. Still, I agree that white blinds are better. This is why most blinds are either white or light colored. StuRat (talk) 02:45, 19 June 2015 (UTC)

I have no reference for this, but surely the difference is between light and shade? Isn't a patio in the shade cooler than the same patio in full sun? I know it's purely intuitive, but there must be some reference for this that cuts the mustard with the scientific community (I presume my OR from the University of No Shit Sherlock doesn't count!) --TammyMoet (talk) 05:34, 19 June 2015 (UTC)

Well, the IPs question is predicated on the fact that the blinds themselves are not shaded from anything, and as they heat up, the energy contained within them is eventually transmitted, at least in part, to the nearby environs. The crux of the answer to their question is that, yes, some of this thermal energy is delivered into the complete system eventually, but some is reflected back out the window and some is held in place (in the blinds themselves or between the the blinds and the windows) long enough that it creates a (small, but in some cases noticeable) reduction on the overall energy required by the AC system to maintain a particular temperature during the hours of operation -- until such time as the ambient temperature surrounding the system cools down or the need for cooling becomes unnecessary for whatever practical reason (i.e. an office building vacated at the end of the day). Snow ^{let's rap} 06:31, 19 June 2015 (UTC)

I'm a bit surprised that no one has pointed out that it's not just reflection that sends heat back out. When the blinds heat up, yes, they radiate heat, but they radiate it equally in both directions. So even if they were perfectly black and didn't reflect at all, they would still reduce the net rate of increase in the heat energy of the room, by radiating it back out the window.

This is the principle used in heavy-duty cryogenic insulation. You can use a Dewar flask to hold your LN2 or whatever, and it works because there's no (or very little) conduction of heat across the vacuum gap, and you reduce the radiative transfer of heat by making the walls mirrored. But still, there's going to be some radiative transfer.

You cut it down by having multiple vacuum gaps, instead of just one. Take the simplest case where you split the vacuum gap with just one extra wall. When the outer wall heats up and delivers a photon into the vacuum gap, it doesn't matter how wide the gap is, it will get to the other end. But if it hits the middle wall, then the middle wall heats up by the equivalent of one photon, and when it radiates one back, it's equally likely to go in either direction. If it goes inward, then it's no different from the case where there's no middle wall. But if it goes outward, then you're back to the outer wall, and various things can happen, none of them worse than the case without the middle wall. So you slow down the overall rate of heat transfer. --Trovatore (talk) 06:51, 19 June 2015 (UTC)

Not to be persnickety or touchy or anything, but I did reference the fact that heat is radiated in both (or rather, all) directions, or at least I alluded to it by noting that some of the heat is transmitted back out the window and some retained in the space between the blinds and the window. Snow ^{let's rap} 07:14, 19 June 2015 (UTC)

You said "reflected", not "radiated". It's possible you meant to include re-radiation; if you say you did, then I'll certainly take your word for it. But you didn't say it. In the context where Nimur had said If the window covering reflects solar energy (instead of absorbing it), then there is less net total energy entering the room, and SemanticMantis followed up by pointing out that there would (almost) always be reflection, I thought it was worth mentioning that, even if the shades are perfect black bodies, absorb all the incident light and reflect none of it, they still slow down the heating of the room. --Trovatore (talk) 07:21, 19 June 2015 (UTC)

(EC) Well, the light is reflected, but the transformed energy generated by an absorbed photon is what generates the heat, so it could only end up there via radiation -- that's why I thought the radiation itself implicit the system I describe. Though to be fair, I suppose its also the case that the glass and the air itself also absorbs some heat. But in any event, all of this raises a notion that is worth repeating again in answering this question -- namely that, aside from the heat that gets transmitted back out the window, or otherwise into the external environment, the overall combined thermal energy of the building and its occupants remains constant. It's simply a matter of how long you can keep some of that energy isolated from the air and other internal environs that actually matter to the occupants enough that they use the AC to begin with. If they were going to spend the rest of their lives in that building and the solar radiation was constant, then the effect of the blinds would be even drastically more negligible. But eventually the day ends and maybe the people also leave the building at the end of the day, so even if the blinds are opened, releasing the air trapped between, and even the blinds radiate all their remaining heat until they reach rough equilibrium with their surroundings, it doesn't really matter so much anymore to the efficiency of the cooling system. Snow ^{let's rap} 07:14, 19 June 2015 (UTC)

Oh, actually on re-reading, you did say something of the sort in your first contribution. But kind of in the middle of a longish discourse. --Trovatore (talk) 07:27, 19 June 2015 (UTC)

Hah, yeah... Maybe I have erred to the side of verbosity in my contributions today. :] Snow ^{let's rap} 07:36, 19 June 2015 (UTC)

Trovatore also seems to have missed my contribution, where I talked about the heat radiating back out the window. Am I typing in invisible ink ? StuRat (talk) 14:27, 19 June 2015 (UTC)

I did miss your comment, Stu, sorry about that. --Trovatore (talk) 19:41, 19 June 2015 (UTC)

Resolved

very interesting reading - thanks to everyone for their responses. (OP on a different IP) 128.229.4.2 (talk) 15:10, 19 June 2015 (UTC)

Happy to help -- I like these kinds of practical every-day context thought experiments. :) Snow ^{let's rap} 22:18, 19 June 2015 (UTC)

The effect is depending on the size of the window. The sun is emitting about 1 kW per square meter or 10 square feet. Much is heat, some is light. Intelligent achritecture arranged glas the way to have much light into the room and less direct sun exposure into the room when summer or in an hot region like a desert or near equator. Feeding the air conditions radiator with cold air taken from a shadow saves also energy by making the ac work on a smaller difference of temperature. --Hans Haase (有问题吗) 09:11, 21 June 2015 (UTC)

Automotive industry is offering special glas to keep the heat out by filtering infrared light. This is very commmon on in the US sold vehicles. Some others just offer colored glas with no effect on infrared light. --Hans Haase (有问题吗) 09:14, 21 June 2015 (UTC)

June 19

TNT equivalent of antiprotons

I was reading this article which explains that it would take 1x10^11 antiprotons to catalyze fusion in a 3 gram pellet of fusion fuel. So I was curious how dangerous that antimatter would be if containment failed, so I want to calculate the TNT equivalent of that much antimatter. According to this, 1 kilogram of antimatter = 21.5 kilotons of tnt. If there are 7x10^14 antiprotons in 1 nanogram then my calculations say that 1x10^11 antiprotons = 3.07 milligrams of TNT equivalent which shouldn't be too dangerous. Are my calculations correct? If a person was holding 3.07 milligrams of TNT and it exploded, would the person be killed? ScienceApe (talk) 03:44, 19 June 2015 (UTC)

Your conversion numbers sound wrong - way too low - and in fact, they aren't even the values provided by the source you linked! Double check your math; you did something wrong. Nimur (talk) 06:26, 19 June 2015 (UTC)

A quick way to remember these numbers is to recall that the Hiroshima bomb released the equivalent energy of about 1 gram of matter. And it was in the neighborhood of 20 kT. So we would be somewhere in the ballpark if it said 21.5 megatons of TNT. (Still off by a factor of 2 or so, though, because a kilogram of antimatter annihilates a kilogram of ordinary matter, meaning you actually release the equivalent of 2 kilograms.) --Trovatore (talk) 06:32, 19 June 2015 (UTC)

Right, so I just need to double my value. So 1x10^11 antiprotons would annihilate with an equal amount of protons, and release 6.14 milligrams of TNT equivalent. ScienceApe (talk) 10:46, 19 June 2015 (UTC)

That site gives the 43 kt number for 2 grams (1+1), which is correct: I get 21.47 kt/g. So I get 7.18 mg TNT from 2×10¹¹ proton masses, which is close enough to twice your value. It's 30.1 J, which is trivial: the only danger might be a burn if it were well enough localized. --Tardis (talk) 09:52, 19 June 2015 (UTC)

I think it is not so trivial. 30 J released in form of ionizing radiation would equal 30 Gray dose if absorbed in kg of matter. The lethal dose for humans is around 6 Gray. If absorbed by the whole body it would give 0.5 Gray dose <-> radiation sickness. Ruslik_Zero 20:14, 19 June 2015 (UTC)

Yeah, this is why the TNT comparison is misleading. If you blow up that tiny amount of TNT, no, I don't think there's any danger (but I take no responsibility for anyone who tries it). But TNT delivers its energy in quite a different way. The TNT equivalence is somewhat meaningful in the context of a bomb, because much of the destruction is in fact delivered by the overpressure and the shockwave, and TNT can also generate overpressure and shock, and total energy is not a bad predictor of how much of those things happen. But right up next to the high-energy particles, it's a different story. --Trovatore (talk) 20:27, 19 June 2015 (UTC)

On reflection, I'm not sure anymore that it would be completely safe to detonate 30 J worth of TNT; the bang might be loud enough to be harmful to your ears. I didn't think of that the first time. --Trovatore (talk) 21:46, 19 June 2015 (UTC)

physics garden

Is a "physics garden" the same thing as a botanical garden. Any differences? --Doug Coldwell (talk) 11:45, 19 June 2015 (UTC)

Do you mean a physic garden? That is a type of herb garden with medicinal plants.--Shantavira|^{feed me} 11:53, 19 June 2015 (UTC)

(ec):It's a "physic garden", using the old term for a medical doctor "a doctor of physick", as in the Chelsea Physic Garden, where plants were grown to supply apothecaries. Mikenorton (talk) 11:54, 19 June 2015 (UTC)

Yes, yes, yes. Ya'all have hit the nail on the head. That does clear it up for me. Thanks!--Doug Coldwell (talk) 11:59, 19 June 2015 (UTC)

I'm pretty sure the use of physic in this case is the same as in the word physician and not the one in the word physicist, though of course they share the same root; but meaningfully diverged in meaning some time ago. --Jayron32 14:12, 19 June 2015 (UTC)

These answers are most useful in my research. Thanks!--Doug Coldwell (talk) 15:19, 19 June 2015 (UTC)

A physic was also a medicine or drug see [15]. People in the north of England used to say in the early 20th century that there was "physic in the sea", meaning that seawater (and bathing in it) had curative properties (see Wakes week#History). The word comes from Middle English at a time when there was no such thing as a physicist. Richerman (talk) 23:28, 19 June 2015 (UTC)

Rather, that branch of applied mathematical methodology that we call "physics" today was historically described as "mathematics" or "natural philosophy." It probably did not really become widely known by the name "physics" until very recently, perhaps as recently as the nineteenth century or even the early twentieth century in some circles. (For example, Henry Cavendish was a philosopher and his publications were printed in the Philosophical Transactions of the Royal Society; but the professorship named in his honor at Cambridge was the Cavendish Professor of Physics. Somewhere between there, "physics" evolved out of "philosophy" in common parlance, referring to the exact same subject matter).

There were physicists long before we had a name or English word for them!

Nimur (talk) 05:52, 20 June 2015 (UTC)

That's what I meant, In the Middle Ages there were Natural philosophers but no Physicists. Richerman (talk) 07:55, 20 June 2015 (UTC)

Nathan Bailey in his 1731 work "The universal etymological English dictionary, Volume 2" has "Physick (ars physica, L.,φύσις Gr,) in a limited and improper sense, it is applied to the science of medicine; the art of curing diseases; and also the medicines prepared for that purpose" compare "Physick, Physicks (φύσις Gr. nature) natural philosophy or physiology, it is the doctrine of natural bodies, their phenomena, causes and effects; their various affections, notions, operations, etc. or is in general the sciences of all material beings or whatsoever concerns the system of the visible world". Mikenorton (talk) 10:39, 20 June 2015 (UTC)

A "physics garden" sounds like someone would be growing calculi. ←Baseball Bugs ^{What's up, Doc?} carrots→ 06:30, 20 June 2015 (UTC)

Why would anyone want to grow Kidney stones ? Richerman (talk) 07:48, 20 June 2015 (UTC)

Maybe there's a shortage. ←Baseball Bugs ^{What's up, Doc?} carrots→ 16:18, 20 June 2015 (UTC)

They make for nice stepping stones in the Liverpool. StuRat (talk) 23:09, 20 June 2015 (UTC)

I went around such a garden recently and it had a big section which had a couple of guards beside it and railings around to stop children as the plants were all extremely dangerous ones like belladonna and mandrake - though what they ever used mandrake for in medicine I'm not sure perhaps they added a few more poisonous ones for effect :) That's the sort of thing they used to grind up to give people in the past. Dmcq (talk) 16:26, 21 June 2015 (UTC)

June 20

Ambulances in japan

Can ambulances in Japan provide advanced life support? I heard years ago they could only provide basic life support due to resistance from doctors? Is this still the case? 2001:268:D005:E2EF:3D19:3D93:82D0:6AA5 (talk) 04:36, 20 June 2015 (UTC)

See Japan’s paramedics in a straitjacket from 2006 and the more detailed Trauma Systems in Japan: History, Present Status and Future Perspectives from 2005. I couldn't see anything more recent. Alansplodge (talk) 18:34, 20 June 2015 (UTC)

Which of these foods are Probiotics?

Ok, I'm this is a serious question and would be happy to have it answered by some knowledgeable folks on here.

Which of these short list of foods are considered specifically "probiotics". I guess it would be most helpful if you could classify each food as either: 1: An excellent probiotic food, 2: Somewhat okay source for probiotics, or 3: Not at all a probiotic food.

• Eggs
• Margarine
• Peanut-butter
• Cream cheese
• Soy
• Ramen soup
• Rice
• Lentils
• Ensure liquid nutritional supplement (that specific brand)

I don't know if a raw/cooked state for some would make a significant difference in the amount of probiotics but if so that would also be helpful to know, thanks very much. 184.65.230.52 (talk) 06:08, 20 June 2015 (UTC)

None. Probiotics are microorganisms such as certain bacteria that normally live in a healthy person's intestines. Some foods, such as live culture yoghurt may contain such organisms, but a foodstuff is not a probiotic itself. Roger (Dodger67) (talk) 06:26, 20 June 2015 (UTC)

From our article: "Scientific evidence to date has been insufficient to substantiate any anti-disease claims or health benefits from consuming probiotics". AndyTheGrump (talk) 06:27, 20 June 2015 (UTC)

Outside the context of that article, however, it's worth qualifying that statement to point out that some of the same organisms that feature in probiotics are utilized in some medical treatments. It's just that these treatments do not involve consuming them; instead, intermediary measures are made to promote the development of the healthy microbiota that normally inhabit the gut. But in any event, I agree with the response below that from the looks of the list, it is quite possible the OP has conflated "macrobiotic" with "probiotic". Snow ^{let's rap} 21:59, 20 June 2015 (UTC)

Googling "what foods are probiotics found in" yields a lot of results, so you could start there. ←Baseball Bugs ^{What's up, Doc?} carrots→ 09:15, 20 June 2015 (UTC)

• See also, fecal transplant. μηδείς (talk) 21:34, 20 June 2015 (UTC)

• I suspect the OP may actually be interested in a macrobiotic diet: "Japanese macrobiotics emphasizes locally grown whole grain cereals, pulses (legumes), vegetables, seaweed, fermented soy products and fruit..."

Biological effects of Radon-222 exposure at 100% concentration

A rather morbid hypothetical question concerning the Radon article's concentration scale: If one managed to inhale pure ²²²Rn (an environmentally-impossible situation, I know), just how quickly would one be "pushing up the daisies" as a result? In other words, what would be the immediate biological effects of exposure at 5.54*10¹⁹ Bq/m³? I assume that asphyxiation would be a comparatively minor concern, considering. DWIII (talk) 07:59, 20 June 2015 (UTC)

I would think it would be about as soon as if you were deprived of oxygen by any other means - not long. Inert gas asphyxiation suggests you'd be out cold within about a minute and brain-dead within about 7 minutes. ←Baseball Bugs ^{What's up, Doc?} carrots→ 09:16, 20 June 2015 (UTC)

It's spelt radon.
Sleigh (talk) 09:40, 20 June 2015 (UTC)

My eyes are not the best. Where is it misspelled here? ←Baseball Bugs ^{What's up, Doc?} carrots→ 09:51, 20 June 2015 (UTC)

I think Sleigh is objecting to the capital R. Tevildo (talk) 10:25, 20 June 2015 (UTC)

Then he should change the article, whose title currently is "Radon". ←Baseball Bugs ^{What's up, Doc?} carrots→ 16:17, 20 June 2015 (UTC)

No, just change the link to radon. Dbfirs 07:39, 21 June 2015 (UTC)

Asphyxia would get you first - see Acute radiation syndrome and Orders of magnitude (radiation). Harry K. Daghlian received about 500 rads and died in 25 days. Louis Slotin received about 300 rads and died in nine days. An operator at United Nuclear Fuels received about 10000 rads and died in 49 hours (this paper, page 34). But, as Bugs has mentioned, lack of oxygen would kill you in a few minutes. Tevildo (talk) 10:10, 20 June 2015 (UTC)

I suppose then we could assume an 80-20 mix (by volume) of radon and oxygen to mitigate against oxygen-deprivation. Given that, we are talking about a radon concentration trillions of times as much as could be found in nature (i.e., build-up in uranium mines). For an 80 kg human and a decay energy of 5.6 MeV per atom, I'm coming up with an estimated 50,000,000 rads per second(!) (quick calculation; I could be wrong). DWIII (talk) 10:36, 20 June 2015 (UTC)

Correction: That calculation is assuming direct contact with an entire cubic meter. Normal breathing (at half a liter per 2 seconds, say) still implies approximately 10,000 rads per second within one's lungs. DWIII (talk) 10:47, 20 June 2015 (UTC)

You can't calculate like that. Rn-222 is almost pure alpha, with only a single gamma emission at 0.51 MeV with a yield of 7.6e-4 (ICRP-07). As for the original question, I'd say the burns would get you first, since for 9.73 kg (1 m³ at standard temperature and pressure) of Rn-222 we're dealing with ~50 MW of decay heat... :-) Kolbasz (talk) 11:41, 20 June 2015 (UTC)

Spot reduction with topical substance

According to the article linked above, local spot reduction (trying to reduce your belly targeting it with specific exercises) is not possible or barely significant, at best.

However, is it possible to reduce a concrete spot with topical gels, creams or lotions? There are many products which claim to reduce fat selectively. Couldn't a substance exist that sends the signal to adipose cells to get rid of fat?--Yppieyei (talk) 14:58, 20 June 2015 (UTC)

Theoretically possible, but it doesn't exist, as far as I know. How would it work, exactly ? Cause the fat cells to die ? Cause them to leak out fat ? Cause them to convert fat into something else ? StuRat (talk) 23:01, 20 June 2015 (UTC)

Density of Graviton?

Hi,
Let intensity of a gravitational field be the amount of gravitational force that a mass creates.
Is there any correlations between Gravitons' density in specific place and the intensity of a gravitational field?
Exx8 (talk) — Preceding undated comment added 15:21, 20 June 2015 (UTC)

The "density" here meaning the number of theoretical gravitons in a given volume ? StuRat (talk) 23:06, 20 June 2015 (UTC)

Someone else here who better understands the subject should arrive to address this question shortly, but in the meantime I will direct you to our Static forces and virtual-particle exchange article for some background on the subject. -- ToE 00:36, 21 June 2015 (UTC)

Perhaps as a lead-in to the graviton question, we can see if there is any similar question which can be properly asked regarding the density (of some sort) of virtual photons mediating a particular electrostatic field. At Stack Exchange, What is the density of virtual photons around a unit charge? received the answer that the density would be infinite due to infrared divergence (which, unlike ultraviolet divergence, does not require renormalization to save the day since measurable quantities remain finite due to the falling energies at longer wavelengths). The reformulated What is the spectral energy density of virtual photons around a unit charge at rest? appears to have been blown off with the equivalent of you can't count virtual particles because they're not real, you silly goose! and a link to Virtual Particles: What are they?. (Our article: Virtual particle.) I'm still trying to digest it all, and hope that one of our subject matter experts will make a timely appearance.

If we can answer (or even figure out how to ask) the parallel electrostatic question, then perhaps we can see what can be answered about the more hypothetical graviton. -- ToE 13:09, 21 June 2015 (UTC)

Need an introductory and generalist engineering book

One that I found is kind of too basic (Engineering Fundamentals: An Introduction to Engineering - Saeed Moaveni ). Others are specialized in one particular discipline. Which would be an Engineering 101 text book? --YX-1000A (talk) 22:36, 20 June 2015 (UTC)

I don't know of one. The only useful engineering book i ever read that wasn't a text was Structures by JE Gordon. Greglocock (talk) 02:56, 21 June 2015 (UTC)

Some of the books that prepare for U.S. Professional Engineering license are pretty good especially for practical understanding use. General engineering across multiple disciplines used to be in the Engineer In Training national exam (Engineers pass two exams along with requisite professional work). I learned more about different engineering fields from the exam prep than school as the topics covered in the exam were not all required in University. NCEES is the parent and controlling organization that sets standards and the books that help are related to those exams. Note that they are broad and practical but lack detail often necessary to meet engineering practice standards that only come from experience. It will demonstrate, for example the engineering and physics of a turbine engine but it's not going to make you competent enough to be a turbine engine design engineer. --DHeyward (talk) 07:02, 21 June 2015 (UTC)

Something like that is exactly that I was searching for. It is clear that it will be necessarily just an overview for the whole field, and not a way of solving real-life engineering problems.--YX-1000A (talk) 13:29, 21 June 2015 (UTC)

June 21

Cases of natural adrenaline halting anaphylaxis

Are there any cases in medical literature where severe anaphylaxis was stopped without medical intervention by the persons body naturally releasing enough adrenaline into their blood stream? Maybe as a result of heightened anxiety or stress from the reaction? 2001:268:D005:E529:B926:913F:AB27:B1C (talk) 05:40, 21 June 2015 (UTC)

Is putting sperm directly into a man's bloodstream a guaranteed way to permanently sterilize him?

This question is purely theoretical for the time being; however, I am genuinely extremely curious about this: Is putting sperm directly into a man's bloodstream a guaranteed way to permanently sterilize him? As in, is this type of male sterilization incapable of ever failing for any male?

Any thoughts on this?

Also, Yes, this is certainly a completely serious question. Futurist110 (talk) 07:28, 21 June 2015 (UTC)

Why would anyone think that is a method of sterilization?--Shantavira|^{feed me} 07:55, 21 June 2015 (UTC)

Because vasectomies can and sometimes do fail? Futurist110 (talk) 08:01, 21 June 2015 (UTC)

Yes, vasectomies fail in a very small percentage of cases but are highly effective otherwise. But the alternate method you suggest has absolutely no evidence in its favor, and is nothing more than a bizarre delusion. Cullen³²⁸ Let's discuss it 08:05, 21 June 2015 (UTC)

I've got a question, though--please pardon any extreme ignorance which I might have in regards to this, but isn't putting a man's sperm into his bloodstream going to cause this man's immune system to reject his sperm? After all, isn't that why some vasectomies are not reversible? Futurist110 (talk) 08:07, 21 June 2015 (UTC)

Also, for what it's worth, I previously saw a similar question here: https://answers.yahoo.com/question/index?qid=20081218192630AA95oVu Futurist110 (talk) 08:09, 21 June 2015 (UTC)

In addition, this Wikipedia article appears to be of value in regards to this: Blood–testis barrier. Futurist110 (talk) 08:28, 21 June 2015 (UTC)

Who was it, some months ago, that asked about injecting an embryo into the bloodstream? ←Baseball Bugs ^{What's up, Doc?} carrots→ 13:17, 21 June 2015 (UTC)

This one: Wikipedia:Reference desk/Archives/Science/2015 April 1 ←Baseball Bugs ^{What's up, Doc?} carrots→ 13:31, 21 June 2015 (UTC)

There is an article, kind of short however, about this - hematospermia.--YX-1000A (talk) 13:26, 21 June 2015 (UTC)

windshield sun shade reflection

Some windshield sun shades reflect sunlight in a colourful manner, like the one shown in http://www.amazon.com/Reflective-Vinyl-Shield-Shade-Window/dp/B006U605YE Is this phenomenon due to Structural coloration, Iridescence, Thin-film optics, or other physical property? Thanks! Etan J. Tal^(talk) 12:46, 21 June 2015 (UTC)

That is iridescence caused by thin film optics. Looie496 (talk) 13:51, 21 June 2015 (UTC)

Thank you! Etan J. Tal^(talk) 14:57, 21 June 2015 (UTC)

Tubes on a salvage tug

What are they for? How are they used? See a picture here: [16] --YX-1000A (talk) 13:50, 21 June 2015 (UTC)

They deflect the prop-wash to blow sediment away from the working area [17] --TrogWoolley (talk) 15:19, 21 June 2015 (UTC)

In marine treasure hunting (and possibly in other forms of marine salvage) they are referred to as mailboxes or mailbox blowers. See How Mailbox blowers work? for construction and operation details. -- ToE 16:16, 21 June 2015 (UTC) Edit: Surprisingly, I've not been able to find them described in any Wikipedia article. -- ToE 16:19, 21 June 2015 (UTC)

Earth compared to the known universe

Suppose the known universe is the size of Earth. How big would our Earth be? The size of a pea? An ink dot? A mite? A speck of stuff on a mite? Anna Frodesiak (talk) 15:13, 21 June 2015 (UTC)

Much smaller than any of those! The diameter of the observable universe (OU) is about 8.8 x 10²⁶ metres, and the diameter of the Earth (E) is 12,742 km or 12,742,000 m. If x is "the diameter of the earth relative to an earth-sized universe" then x/E = E/OU, or x = E²/OU, which is about 1.84x10^-13 m, or 184 femtometres (fm). For comparison, the Bohr radius - essentially the radius of a Hydrogen atom - is about 52600 fm, or about 285 times as big. Space is big. Really big. AndrewWTaylor (talk) 15:58, 21 June 2015 (UTC)

I concur with your calculation and add that 184 fm is about 12 times larger than the 15 fm diameter nucleus of a uranium atom and 120 times larger than the 1.5 fm diameter of a hydrogen nucleus (a single proton). So, smaller than an atom, but larger than an atomic nucleus. -- ToE 16:04, 21 June 2015 (UTC) Edit: Article of interest: Orders of magnitude (length). -- ToE 16:08, 21 June 2015 (UTC)

In addition,universe is in its initial stage of rapid expansion...sidsandyy