Wikipedia:Reference desk/Archives/Science/2013 September 29

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September 29

Raisins as cough suppressant?

Hello all, I want to ask you about a strange observation I made the other day: I've been sick for the past couple days and coughing quite a bit; however, the other day, after I ate salad with (raw) raisins in it, my cough and sore throat temporarily disappeared almost immediately! I also observed the same effect later on, after eating boiled rice with (stir-fried) raisins. Which raises the question: What is it about raisins that makes them effective as cough suppressant? 24.23.196.85 (talk) 6:59 pm, Today (UTC−4)

Googling this question provides no evidence raisins are cough suppressants as such. μηδείς (talk) 03:09, 29 September 2013 (UTC)

Eating almost anything when you have a cold can temporarily purge your throat of gunky stuff that builds up. (How's that for techie terminology?) ←Baseball Bugs ^{What's up, Doc?} carrots→ 03:16, 29 September 2013 (UTC)

The name of a medical condition

First and foremost, this is not a medical question. So, here goes: when I was a teen, there was a family that seemed to have some form of genetic abnormality. Generally, all of the members were short and quite muscular. In fact, my friend went by the nickname "Caveman." As I understand it, he and his brothers entered puberty when they were about 6 years old. They began to develop facial and pubic hair, their testicles descended, voice became deeper, etc. In short, they were physically mature by age 8 (though of short but very muscular stature). They were neither midgets nor dwarfs. Is there a name for this condition? 173.35.158.194 (talk) 01:12, 29 September 2013 (UTC)

Define "short". One thing I know from observation is that those who mature earlier than average seem to be shorter - like their "growth spurt" got too early of a start. Maybe "early maturity" or something like that? ←Baseball Bugs ^{What's up, Doc?} carrots→ 02:28, 29 September 2013 (UTC)

We can't know what the specific cause of your friend's condition was, but our article on the topic is Precocious puberty. Deor (talk) 02:55, 29 September 2013 (UTC)

My friend was about 3 feet 11 inches. His brother was a bit taller but generally everyone in his family (i.e. siblings) were all well below the average. His musculature was also very well defined and he even had a bit of a brow ridge. I will read the article Jack suggested. 173.35.158.194 (talk) 04:08, 29 September 2013 (UTC)

Jack has had jack all to do with this question. -- Jack of Oz ^{[pleasantries]} 04:46, 29 September 2013 (UTC)

The OP said nothing about anything remotely like this
The following discussion has been closed. Please do not modify it.
How did your young neighbors' balls feel when you palpated them? Did they hang evenly? Were they sore? Did you have them turn and cough? Where there differences between the boys' ball, left from right or boy to boy? Did they fit in you teenage hands, or where they overlarge? How did they smell? Were they symmetrical? Did they have the same internal texture? μηδείς (talk) 04:50, 29 September 2013 (UTC) I haven't been fiddling with my neighbour's balls lately, but you'll be the first to know when I do. -- Jack of Oz [pleasantries] 05:33, 29 September 2013 (UTC) That was the indentation of laterness, not the indentation of personal address. μηδείς (talk) 20:17, 30 September 2013 (UTC) Where can I read an article about your invention called "the indentation of laterness"? -- Jack of Oz [pleasantries] 21:53, 1 October 2013 (UTC)

When I was at primary school, one of my classmates also started to develop rapidly, his hair started greying aged 8 and he got wrinkles about the same age. I was told then it was progeria. I wonder if this is the condition the OP refers to? --TammyMoet (talk) 08:46, 29 September 2013 (UTC)

The OP speculates on a genetic link, mentions that all family members were short, but specifies that his friend and his brothers were affected by symptoms such as the early development of secondary sex characteristics. Familial male-limited precocious puberty is a type of precocious puberty affecting the males in a family; those with the condition tend to be short as adults because their accelerated development means they stop growing sooner than their peers. This article provides an overview of the genetic mechanism and some useful links. We can't know whether the OP's friend had this condition, but if so then yes, it has a name. - Karenjc (talk) 14:41, 29 September 2013 (UTC)

To correct one point - in human males the testicles normally descend before birth see [1]. Richerman (talk) 22:31, 29 September 2013 (UTC)

The answers above got this already, but I should point out precocious puberty is an article. Wnt (talk) 16:57, 1 October 2013 (UTC)

Why do we feel colder when lying down?

You're sitting in an armchair watching TV, reading a book, whatever. You're perfectly comfortable, temperature-wise. Then you decide you feel like lying on the even more comfortable sofa and continuing your reading/watching in the supine position. But within a few seconds of lying down you realise you now need a blanket or some cover because you feel cold. The room hasn't changed, the heating arrangements (if any) haven't changed, your clothing hasn't changed, but you still feel colder lying down than you did when you were sitting in a chair.

Why? -- Jack of Oz ^{[pleasantries]} 03:44, 29 September 2013 (UTC)

This discussion has been closed. Please do not modify it.
The following discussion has been closed. Please do not modify it.
This is a totally wild guess, so delete it if it sounds absurd - but could it be that you're more "bunched up" when sitting up, and more "spread out" when lying down, i.e. exposing more of your surface area? Or that maybe your heart becomes a little less active, as it would at night? How often, for example, have you gone to sleep with the cover off and awakened with it on? ←Baseball Bugs What's up, Doc? carrots→ 03:52, 29 September 2013 (UTC) It's not a question of absurdity or otherwise, but I thought it was thoroughly understood by now that guesses of any kind, but particularly wild ones, are the complete antithesis of what the Reference Desk is all about. -- Jack of Oz [pleasantries] 03:57, 29 September 2013 (UTC)

It's easy to find out where the immediate effect comes from, just go lie down on the floor right now and concentrate on where the cold is actually coming from. Clearly what you feel is that while you do start to feel cold generally, the cold is coming from the floor. And that can be easily explained, when you are sitting your clothes will have reached some equilibrium temperature. Your body is in dynamic equilibrium where the heat it produces leakes out into the environment. As much heats enters your clothes per unit time as is dumped by your clothes into the environment, which means that you clothes, while cooler than your body temperature, will be warmer than the environment.

When you lie down on the floor, you will make thermal contact with the floor, the part of the clothes in contact with the floor will cool down. More heat will have to be transported to the floor before a new dynamic equilibrium is reached, the part of the floor directly below you will have to heat up a bit. Whether you will feel warmer or colder on the longer term depends on how efficiently heat is transported away in this new situation compared to the old situation.

In winter you will get the same effect when putting on your winter clothes before going outside. These clothes will initially be at room temperature and you will feel quite cold immediately after putting on all your heavy winter gear (if you do this fast). Count Iblis (talk) 13:59, 29 September 2013 (UTC)

Interesting points. Jack could test this in a different way: Lie on the couch from the get-go, until it feels warm. Then get up and sit in the chair. I would bet a good portion of a dollar that the chair will feel cold. ←Baseball Bugs ^{What's up, Doc?} carrots→ 17:11, 29 September 2013 (UTC)

Another thing to consider is that more muscles are relaxed when lying down. So less energy is burnt to maintain the posture. Graeme Bartlett (talk) 22:28, 29 September 2013 (UTC)

Hot air rises...if there is any source of cold air (eg a draft), then the cooler air would pool lower in the room. That could be a contributory factor. SteveBaker (talk) 04:38, 30 September 2013 (UTC)

Assume the room is completely sealed and there are no drafts. I don't experience this effect if I simply move to a different chair, only if I go from the sitting position to the lying position. -- Jack of Oz ^{[pleasantries]} 20:18, 30 September 2013 (UTC)

When sitting on a chair only a small part of your body is in contact with the chair, if you lie down, it's half your total body surface. If you hold yourself in a push-up position for a minute with your belly just a millimeter above the floor, you won't feel cold. The moment you make contact with the floor you'll start to feel cold. Count Iblis (talk) 22:43, 30 September 2013 (UTC)

I get the picture now, and thanks all, but I won't be trying the push-up test any time soon. Actual physical activity - er, yuck.  :) -- Jack of Oz ^{[pleasantries]}

How to accurately measure how long someone has lived

Given the bones of Li Qing Yun, can it be determined when he was born? Count Iblis (talk) 17:10, 29 September 2013 (UTC)

Radiocarbon dating might be useful for this purpose. DavidLeighEllis (talk) 22:32, 29 September 2013 (UTC)

the teeth might contain some earlier material, but if he really was as old as claimed, there are likely no teeth left! Graeme Bartlett (talk) 22:38, 29 September 2013 (UTC)

I was gonna say radiocarbon dating, but this method is only reliable for telling when someone died -- it's not so reliable for assessing when someone was born. 24.23.196.85 (talk) 22:51, 29 September 2013 (UTC)

Our article says that he produced over 200 descendants during his life span. One could perhaps try to find the remains of his children (using DNA analysis one can verify this), and one can determine when each child died. That would then give a lower limit to his age. Count Iblis (talk) 00:56, 30 September 2013 (UTC)

The problem with bones is that they are remodelled throughout life; slowest in cortical bones, 2%-3% pear year according to this source. Cartilage, on the other hand, seems to stay more or less the same throughout adult life. So if some cartilage is preserved, radiocarbon dating of the DNA of chondrocytes might be possible. Icek (talk) 11:55, 30 September 2013 (UTC)

Hypothermia

OK, this might sound unbelievable, but here goes: I've recently watched an interview with Leonid Bronevoy, where he talked (among other things) about his father who was sent to the Gulag for being a Trotskyite. Well anyway, they sent him to chop wood in some godforsaken place in eastern Siberia, and the foreman of his work crew was a sailor from the cruiser Aurora, who was probably in the Gulag for being too principled and not accepting Stalin's usurpation of power. So the story goes, one frigid winter day when the temperature was -50 degrees, a bunch of fresh fishes arrived, and Bronevoy's father recognized one of them to be his interrogator (this was probably soon after Beria replaced Yezhov, so many of the KGB agents who served under Yezhov were themselves executed or sent to prison). He told this to his foreman, and what the foreman did was very clever (apparently the same agent interrogated the foreman, too): When the interrogator asked to join his crew (a singularly stupid request on his part -- what was he thinking?!), the foreman replied, "No problem, I forgive you, you're welcome here" and put him to work right away; of course, the KGB agent, being unused to physical work, quickly got tired, and when Bronevoy's father noticed that the new guy wasn't keeping up with the work and reported this to the foreman, the foreman gave the chekist permission to take a break, WITHOUT warning him of the need to keep active in order to prevent hypothermia. Anyway, when the two of them came back to the chekist later, not only was he dead, but he was frozen so solid that when one of them struck him with the haft of an ax, he actually shattered into tiny little pieces. My question is: Is this even halfway-plausible, or was Bronevoy making this up? I know that one can easily die from hypothermia in such extreme cold, but is it possible to actually freeze so solid as to shatter??? 24.23.196.85 (talk) 22:41, 29 September 2013 (UTC)

Given the proportion of the human body which is comprised of water, and the fact that ice can shatter, the story seems plausible. DavidLeighEllis (talk) 22:58, 29 September 2013 (UTC)

From information at The Straight Dope, it doesn't sound like human bodies will shatter even at cryogenic temperatures. Red Act (talk) 23:06, 29 September 2013 (UTC)

I doubt a human being could freeze to that degree of brittleness in nature (if at all). At any rate, cryo-shattering is a thing done in cooking, see here [2], [3], [4], and [5]. These: [6], [7], [8], [9], [10], [11], [12], and [13] all suggest that meat, fruit, chees, and fish can shatter, become brittle, etc. Here's a video of cryo-shattering salmon: [14]. From experience, if you throw a frozen hamburger hard enough, it will break, maybe not into a million pieces, but it fractures in a way that could be described as shattering. However, while this all seems to imply that a human could shatter, I want to stress that it would be under very unnatural circumstances- if you completely froze a person at extremely low temperatures, they'd probably shatter if enough force was used; but nature, or a brief exposure to liquid nitrogen, wouldn't suffice to freeze them to that degree. NOTE: This is not a subject I had prior familiarity with, don't trust my judgement (especially since I'm going with an educated guess based off of the links).Phoenixia1177 (talk) 00:56, 30 September 2013 (UTC)

The Straight Dope may be a great site, but against us they have met their match. Obviously Phoenix deserves our thanks for nailing this, but I'll add that meanwhile I found http://www.youtube.com/watch?v=zLWEemhtdbE and http://www.youtube.com/watch?v=xtHGGPseUqA . The shattering is not as dramatic as filmmakers might imagine it, but it is easy to picture someone swinging an axe and cracking off an arm or even a piece of torso. While Russian winter winds are not as cold as liquid nitrogen, they pass a tremendous volume of cold air quickly past the body, so I can picture it could freeze relatively quickly. The only question is whether the less-than-cryogenic freezing is enough to change the properties of the flesh, and that I can't quite answer. Wnt (talk) 06:11, 30 September 2013 (UTC)

It might be instructive to investigate the gruesome details of the death of Payne Stewart and his associates on an airplane that lost cabin pressure at a high altitude. As I recall, it was difficult to identify body parts of specific persons, and that Stewart's coffin contained only a few bones. Presumably the bodies on board had been frozen as solid as with the OP's premise, yet some bones survived the impact of an airplane crash, which would be way much more force than swinging an axe would be. ←Baseball Bugs ^{What's up, Doc?} carrots→ 08:34, 30 September 2013 (UTC)

Promession is a proposed method of disposing of corpses by freeze-drying, where the body is frozen with liquid nitrogen and then shattered by vibration (and then there's some additional tidying-up). AndrewWTaylor (talk) 10:20, 30 September 2013 (UTC)

It seems very unlikely that physical activity could make the difference between staying alive and freezing solid in less than a day. For a body to freeze, it would have to cool at least 37°C. Let's assume the body has a thermal mass equivalent of 45 kg water, that would mean losing 45*37= 1665 kcal of heat. In the time it takes a dead body to give off that much heat, a living person would have expended even more, because he has to maintain his high body temperature. Considering that an average daily energy intake for a man is about 2500 kcal, that food rations at the gulag won't have been generous, that "shattering" of the body would not happen at 0°C but much lower, meaning more cooling and implicitly more heat expended by living persons in the same conditions, it seems very implausible that such an event could have happened in mere hours like the story suggests. The conditions required would be so hard that few could survive the day, and even if they survived their energy reserves would be depleted after a few days or weeks. Ssscienccce (talk) 10:31, 30 September 2013 (UTC)

I'd like to make a simple request. Can those posting temperatures here please clarify whether they mean Celsius or Fahrenheit? HiLo48 (talk) 11:07, 30 September 2013 (UTC)

The only ambiguous temperature mentioned, as far as I can see, is the -50 degrees of the OP. Given that the source was an interview, it may not have specified the temperature scale, but since Celcius and Fahrenheit values coincide at -40°, the difference is relatively small: either -50°C = -58°F or -45°C = - 50°F Ssscienccce (talk) 12:06, 30 September 2013 (UTC)

Since the interviewee was Russian, it's safe to assume he meant Celsius. 24.23.196.85 (talk) 03:26, 1 October 2013 (UTC)

Note that the reason frozen people doesn't readily shatter is the fat they contain. Fats freeze solid at a considerably lower temperature than water. Unlike water, they don't freeze at one temperature, but get gradually thicker and then harder as the temperature drops. Becoming hard enough to shatter requires that they be far colder than when they first start to solidify. You can do an experiment, and cut a chunk of fat off a piece of meat, or maybe use a pat of butter. Put it in the freezer, then try to shatter it with a hammer. Do it outside, as this will make a mess. If you want to try it at colder temps, buy some dry ice and put it in that before you try to shatter it. Many grocery stores carry dry ice. StuRat (talk) 17:30, 30 September 2013 (UTC)

total current in parallel cct

hello, i am stuck on this question:

if four 100 W lamps are connected in parallel across a 120 V source, what is the total current? a) 833 mA b) 3.33A c) 33.3A d) 8.33 A

i dont even know where to begin, help is appreciated. — Preceding unsigned comment added by 208.96.87.57 (talk) 22:56, 29 September 2013 (UTC) unless, is it I(t) = V(t)/R(t)? which is 100/120 = 833mA?

We apply ohms law, E = IR, where E is voltage, I is current, and R is resistance, and the definition of the watt as EI. Now, we determine the amperage of a 100 watt, 120 volt lamp as using W = EI, where W is watts. Thus, W/E = I, so 100/120 = 0.8333... is the amperage of an individual bulb at 120v. But there are four bulbs in parallel, so the total current is (100/120)*4 = 3.333... amps. DavidLeighEllis (talk) 23:12, 29 September 2013 (UTC)

ah yes yes yes thank you, this makes perfect sense.208.96.87.57 (talk) 23:22, 29 September 2013 (UTC)

remember, when you don't know the answer, always choose B. Gzuckier (talk) 05:31, 30 September 2013 (UTC)

Minors' calorie count

Health-related question. Is there a way to figure out how many calories a given minor should consume in a day? All the sources I've found online say that their systems would only apply to adults. Theskinnytypist (talk) 23:51, 29 September 2013 (UTC)

Use Google and search on calorie needs for kids, and you'll get heaps of sites. http://www.weightlossresources.co.uk/children/nutrition_calorie_needs.htm has a good table and information:-

   Calories per day
   ================
 Age       Boys    Girls
------     -----   -----  
 1– 3      1,230   1,165 
 4– 6      1,715   1,545 
 7–10      1,970   1,740 
11–14      2,220   1,845 
15–18      2,755   2,110 
Adults     2,550   1,940 

This can only be a very rough guide designed to keep you skinny and assuming not a lot of exercise. For instance, I am in my 70's, only moderately overweight (80 kg) and eat about 6000 calories per day. How do you format a table in this thing?

121.215.63.7 (talk) 01:13, 30 September 2013 (UTC)

There is a formal table, but I find it easier just to put a space in front and space them out myself. I did this for you above. StuRat (talk) 17:21, 30 September 2013 (UTC)

Thank you, Mr StuRat. 58.164.224.95 (talk) 23:46, 30 September 2013 (UTC)

Anyone know why at every age the suggested calories is lower for girls than for boys? Aren't girls as big or bigger than boys at some ages? Duoduoduo (talk) 15:37, 30 September 2013 (UTC)

Boys have a faster metabolism due to (on average) more muscles and less fat. Count Iblis (talk) 18:10, 30 September 2013 (UTC)

Is that true for pre-pubescent boys vs. girls -- more muscles and less fat? Duoduoduo (talk) 19:04, 30 September 2013 (UTC)

I don't think it is. However, boys might tend to be more physically active, engaging in sports and such, but this may vary by culture. StuRat (talk) 22:21, 30 September 2013 (UTC)

I agree with 121.215.63.7 that the calories are quite low, but then the average child's physical activity is way below what is recommended, and that recommendation is already way too low. The best way one can make sure a child is not going to get obese is to make sure the child gets plenty of exercise every day. At the very least the child needs 2 hours of play time per day which must involve one hour of running, or other strenuous physical activity. Count Iblis (talk) 18:10, 30 September 2013 (UTC)

Agree 100%. It is widely regarded by health experts that the "baby boomer" generation (ie people born in the 10 years or so in the economic boom after World War 2) are the most healthy generation ever, and each generation after is less healthy, with life spans falling. When I was a kid (1940's & early 1950's), we spent almost the whole day outside doing physical things - mowing lawns and other chores by parent command, physical games with other kids. We walked or cycled to & from school, regardless of distance. If we wanted to /were invited to visit a friend after school or on a weekend, we walked or used our bikes, up to a hour if the distance required it. Same for kids in the 1960's. None of this happens with today's kids. They don't play outside and parents drive them everywhere. But today's kids don't get much mental exercise either. When I was a kid, I had my own "lab" in the backyard, where all manner of chemistry, electrical/radio, and mechanical experiments and devices were worked on. This was not at all unusual - many of my friends had much the same thing. Chemist shops (= "drug store" in USA) used to sell chemicals & other stuff in small quantities to kids. But it's unheard of today. When I was 12, I pooled my money (which I had earnt doing odd jobs - more walking and physical activity) with 4 other kids and bought an old car. It was an ancient clapped out wreck but we had a lot of fun figuring out how to make it go when it didn't. Again, not unusual at that time. Kids back then got a lot more experience with responsibility too. Outside of school, mealtimes, and parent commanded chores, the whole day was ours and we did what we liked, with no adult around. Todays' kids get their day totally structured, controlled, and supervised by parents and other adults. 58.164.224.95 (talk) 00:18, 1 October 2013 (UTC)

Citation needed. Look at the life expectancy history graph: [15]. All the kids in my neighborhood spend tons of time running around together in unstructured play. Growing up in the 90's and early 2000's we did too, and I knew kids who worked on old cars and snowmobiles for fun with money they earned themselves. My friends and I built robots. Everyone also played video games and socialied online, but I can't think of anyone I knew who didn't spend lots of time active outdoors. Katie R (talk) 11:55, 1 October 2013 (UTC)

It was mentioned in a BBC science program some time ago that the average fitness level of children has declined by an enormous amount. In the typical school class, the best Cooper test scores of today are similar to the average scores in the 1980s. Count Iblis (talk) 14:20, 1 October 2013 (UTC)

Katie, you have cited Wolfam Alpha data as showing that lifespans are not now falling. Unfortunately, we can't tell where they got the data from. There are two things to keep in mind: a) when you see things like "average life span", that is gnerally obtained by averaging the age at death for all deaths. This means that infant mortality, which until recent decades has been quite high, and road deaths, which are biased towards teenagers and young adults, skew the result. If you disregard deaths occurring at age 2 and below, it changes the picture somewhat. In earlier decades, if you lived beyond 2 years, you generally made it into adulthood. If you didn't get get killed in a car accident or fighting in WW1 or WW2, you lived a rather long life. b) As the natural life sapn of a human appears to be about 90+ years, you can only quote a measured value for folk born before about 1920. Clearly, for today's generation of kids and teenagers, the lifespan is a prediction. And the growing consensus of expert predictions is that they won't live very long, and they certainly won't be fit.

If you had friends who worked on cars, built robots, etc, great. I trust the robots were of some significance and not just simple models built to prescibed designs out of Lego - they don't count. It is well known that people of my generation and the next were commonly into physical and intellectual pursuits as in cars and labs in the back yard. It is quite unusual now. You can no longer buy chemistry sets or individual chemicals at local retail. There is no longer the demand. The media is full of articles about diabetes in children, due to obesity. 30 years ago, you hardly ever saw an obese child, though every scholl had a "Fat Kid". diabetes back then was only a not-so common disease of the middle aged and beyond.

On the intellect side, I get to interview folk, young and not so young, for jobs in the technical/engineering field. A sample question: "If I have a litre of gas at 30 C and raise it to 60 C, what will be the change in pressure?

• Typical answer 1970's young lad: "Err, an increase of, ah, about 10%".
• Typical answer 1990's young lad or lass: "It doubles." Me, "What about raising it for 30 F to 60 F?" Young lad: "What?, oh, I forgot, you need to proportion from absolute zero. Er, ah, mumble, er, can I have a calculator?"
• Typical answer 2013 young lad or lass: "I dunno." Me: "Did you study Gay-Lussac's law in science?" Young lad/lass: "We might have, I forget." Me: "It's the law about proportionality of pressure and temperature, based on the kinetic theory of gasses." Lad/lass: "Yes." Me: "so, what will be the change in pressure?". Young lad/lass: "I dunno."

And they and their teachers wonder why I hire the older ones, or get someone from an Asian or former iron curtain country. 58.164.224.95 (talk) 15:21, 1 October 2013 (UTC)

I think kids today would say (or rather text) "LOL, tchr sed 'gay, loose sack' ! ". StuRat (talk) 10:10, 2 October 2013 (UTC)

You can check sources at the bottom of the page, although it also comes with a disclaimer saying that those might not be the specific source of the data for the query. I would be interested in seeing data with infant mortality and non health-related deaths filtered out. What's bothering me about your post is that you're just making assertions about the way things are without backing it up. You listed all the things kids did when you grew up and stated that kids don't do much outside, have unstructured play or have interesting intellectual activities on their own. My personal experience contradicts that, so I shared. I wouldn't be surprised to hear that children are more sedentary, although that doesn't mean they aren't buidling intellectual skills - I spent a lot of time on the computer as a kid, programming my robots or just researching whatever was interesting me at the time. Sometimes I would experiment with mechanics, other times I would design and program a simulation to test an idea instead. If you have good sources documenting the decline of different activities and their effects on health and intellect then share them, but don't just state your own opinion on it as fact. Katie R (talk) 16:05, 1 October 2013 (UTC)

The change in what kids do, and the decline in their health, has been covered so much in newspapers in the last couple of years, I had assumed I was just reciting what everyone knows. It will take some time to dig up specific references, as one tends to read the daily newspaper feature articles and then throw them away. I may list them on your talk page. My assertion that intelectual capacities are dropping has not been covered so extensively, but the evidence is never the less there - employers and universities keep complaining about it, and high school science teachers tend to clain they need to drop standards and make it more entertaining in order to get kids to get anywhere with science education. Again, because of the time factor, I may provide citations on your talk page. 58.164.224.95 (talk) 23:30, 1 October 2013 (UTC)

The main health claim I'm interested in is the declining life expectancy - I'm familiar with the sorts of headlines you mentioned, but I don't think I have heard that particular claim. I would be much more interested in sources that cite specific studies (or links to the studies themselves), rather than the "researchers at X university announce" stories that make big claims but seem very light on the science. Sorry if I've come off a bit argumentative - it's not really an excuse, but I had a rough couple of days and I think I let my mood affect this thread more than I should have. By the way, it doesn't hurt to add references to a thread after it has been archived - it still helps if someone runs into the thread through a search later on. Katie R (talk) 11:54, 2 October 2013 (UTC)

Hey, Katie, there's absolutely no need to apologise for your post. You've only made a not unreasonable request for references. Unfortunately, there are certain people on that frequent the Reference Desk that are 1000% worse in their argumentative or prima donna attitudes. And those turkeys that delete posts they don't like, psuedo-justifying their vandalism on the talk pages. And other turkeys that just silently delete what they don't like. How do you add references to an archived post? There are no clickable edit buttons for archived questions. 121.215.151.241 (talk) 00:01, 4 October 2013 (UTC)