title list | over_18 list | post_content stringlengths 0 9.37k ⌀ | C1 list | C2 list | C3 list |
|---|---|---|---|---|---|
[
"Why are small animals like spiders and scorpions sometimes so incredibly venomous? Given the size of their prey, why would they require such potent venom?"
] | [
false
] | It doesn't make sense to me that something smaller than the palm of my hand would need a venom so lethal that it could kill a grown adult, considering the size of their prey (which is pretty close to their own size or smaller usually). Why can't they just use smaller doses or a less potent venom instead? (examples - , ... | [
"Most highly venomous and poisonous animals co-evolve with another species that evolves an ever-increasing tolerance to the venom. Think of it as an ever increasing evolutionary arms race, so to speak. ",
"For example, the rough-skinned newt, a highly poisonous newt that lives in North American, has enough poison... | [
"I noticed you said \"highly venomous newt\" then \"has enough poison.\" Just to clarify, I thought it was:",
"Venom: Animal bites you",
"\nPoison: You bite animal",
"Does this go hand-in-hand with this case? Ingesting the venom is poisonous to humans?"
] | [
"I thought venoms were usually proteins, which means you could eat them and your stomach acids would denature them without them hurting you. (Neglecting diffusion through the esophageal tract and such.)"
] |
[
"Can it be Too humid in a house during the winter?"
] | [
false
] | null | [
"I didn't think I would get sick from too much moisture in the house, but that report worried me. I like the moisture in the house, no static electricity. Thanks for the feedback."
] | [
"Humidifier are the way to go. there's ones that let you control the level of humidity to prevent mold. "
] | [
"I doubt you can make yourself sick with too much moisture, considering during the summer you can get near 100% humidity at these same temperatures ~70-80F. I also don't think you need to look for an alternative, since different ways of getting moisture into the air shouldn't affect the outcome much. The difference... |
[
"Does the moon being overhead affect your weight on Earth?"
] | [
false
] | If you stand on a shoreline, do you weigh (ie force downwards to Earth) more at low tide than high tide, because the moon is closer at high tide and thus exerting a force on you in an upward direction? | [
"Yes, it does, but not by very much. The gravity you feel due to the Moon is approximately 3 * 10",
" m/s",
" , compared to about 9.8 m/s",
" due to the Earth, or about 0.0003% of the strength."
] | [
"What mass of sofa are you using? Guesstimating a sofa at 50kg, that gives you gravity of 10",
" m/s",
" , a ten thousandth of the force from the Moon."
] | [
"I mean, obviously a sofa ten-thousand times heavier than the one you used..."
] |
[
"How far would the ocean drop if all the fish etc. suddenly vanished?"
] | [
false
] | Not including the single celled organisms and all that but the general human-eyeable things. Essentially, what is the volume of all those swimmy things and how much beach would we inherit if they all disappeared? | [
" A few microns. ",
" Let's talk about ",
"biomass.",
"\nDifferent people give different estimates, but we can probably get this to an order of magnitude. ",
"For reference, humans (all seven billion of us) put together have about 100 million tons of dry biomass, which is basically a measure of our weight w... | [
"Ho-lee shit, man! That's an incredible amount of detail, thank you so much! We've all had this long week working out in CO, took part in a bit of the local flora and came up with that just now so thank you for being so prompt and thorough! Another reason to love this community (and science)! We were all expecting ... | [
"Oceans are weird. See, on land most of the dry biomass is tied up in plants, and specifically in wood and roots. You've got a big pile of plant biomass for every animal in that form.",
"In the oceans, you don't have much in the way of big plants. You've just got planktonic algae. Their total biomass is relat... |
[
"What would be a viable lubricant to -85F?"
] | [
false
] | There is a viral video for a gun lubricant, Liberty Lube, that claims it functions to -85F. The video demonstrates it squeezing from the dispenser after freezing in dry ice, while synthetic motor oils and other lubricants are solid. What could this possibly be made of? | [
"Their MSDS page is blank!",
" ",
"MSDSs are extremely useful OSHA-mandated documents describing safe handling, poison control procedures, and what is actually in a product if you are curious.",
"This",
" is the MSDS for a functionally similar competitor, although this brand only advertises itself down to -... | [
"To be specific, poly(1-decene) is a polymer. I'm assuming it's a fairly small molecular weight polymer at that, and it seems to be dissolved in 2-ethylhexylacetate. I wonder if we'd be able to find a molecular weight range for the polymer specifically used in these two examples."
] | [
"Wicked Smaht. Thanks!"
] |
[
"How do devices tell how much battery is left?"
] | [
false
] | How do things like my phone know what percentage of battery life I have remaining? | [
"Most people think a battery provides a constant voltage while it discharges. This is not the case. In fact, the voltage decreases as it empties, according to a fairly predictable curve. In general, this curve looks ",
"something like this",
". ",
"From there, it becomes fairly easy for Apple, (or Samsung... | [
"There are actually a lot of different ways.",
"Voltage is a good indicator of %charge, but not a good indicator of remaining capacity (since remaining capacity will change with time).",
"Most modern electronics with lithium-based batteries actually use a combination of metrics to provide an accurate estimation... | [
"So do they time it or is there an instrument in the device that measures voltage?"
] |
[
"Is there a limit to earthquake magnitude? How big can an earthquake get?"
] | [
false
] | The biggest earthquake recorded was the which was 9.5 on the moment magnitude scale. There have been 4 other earthquakes over 9.0 in the last 60 years or so (Alaska, Indonesia, Russia and Japan). These events seem very common on a geological timescale. How big could a once-in-a-million-years event be? Is there any geol... | [
"Please don't ",
"plagiarize directly from other sources",
". "
] | [
"There is no theorical limit to the magnitude of an earthquake per say, but there is a physical limit to it as there is a finite amount of earth crust that can move to produce the quake. As an exemple to the absence of a theorical limit, the estimated magnitude of the starquake on the magnetar SGR 1806-20 was 32.0 ... | [
"If you were trying to prove a point, you didn't make that point very clear. You could have linked to the page you got it from, or stated your objections to the question. Instead you pasted as your own a scientific explanation that you didn't write.",
"Moreover, the point of AskScience isn't to answer questions... |
[
"Politics aside, is there any scientific evidence behind Todd Akin's claim that the female reproductive system shuts down in cases of rape?"
] | [
false
] | null | [
"No. ~5% of rape victims conceive. ",
"source"
] | [
"Cheers. Makes you wonder who these doctors are that are providing politicians with their scientific knowledge. "
] | [
"Most likely physicians that are in part-time practices and devote some time to lobbying for reform they want. Most likely older. Most likely not up to date. Most important, they are most likely speaking beyond the realm of their expertise...i.e. whoever said this most likely was not an ob/gyn. They could be fa... |
[
"How did we determine the shape of electron orbitals?"
] | [
false
] | [deleted] | [
"The \"shapes\" you are referring to are probably the probability densities as a function of spatial coordinates. It's a postulate of quantum mechanics that the state of a particle is represented by a wavefunction, and that the modulus squared of the wavefunction is the probability density.",
"The wavefunctions f... | [
"It comes from the standing wave solutions to the Schroedinger wave equation in 3D with a coulomb potential.",
"If you have a system described by a 1D wave, like a violin string, then the standing waves are ",
"sine functions",
". These solutions have an integer number of nodes where the function is always ze... | [
"I'll let you in on a little secret: we don't know the shape of the electron orbitals beyond hydrogen. Not exactly, anyway.",
"Quantum Mechanics is hard. I don't mean in the sense that it's difficult to understand, which it is, but it's difficult in a mathematical sense, too. The only system for which we can solv... |
[
"Is there a known reason why there are no multicellular prokaryotes? Could there be?"
] | [
false
] | I guess I'm confused about the transition from single-cellular to multi-cellular. Is there any reason that a nucleus is absolutely necessary for that? Thanks in advance. | [
"Well, depending on how you define \"multicellular\", there might be some prokaryotes that actually do qualify:",
"http://blogs.scientificamerican.com/lab-rat/bacteria-with-bodies-multicellular-prokaryotes/",
"But we do have far more multicellular eukaryotes. The nucleus allows much higher degree of regulation ... | [
"There actually are some \"multi-cellular\" prokaryotes, depending on how you define multi-cellularity. You might want to read up on filamentous prokaryotes. This is essentially when bacteria don't completely separate when they multiply, and thus end up producing long branching strings of bacteria. The structures e... | [
"The specialization is partly because there is a nucleus and partly because eukaryotes evolved more mechanisms for epigenetic control of gene expression. If you have a nucleus, you don't start to translate RNA as soon as its made. That allows for splicing, or essentially chopping the RNA into different forms. It al... |
[
"If a person gets an organ transplant (and assuming their body doesn't reject it) is there a point, after the body's cells have been refreshed with new ones, in which the replacement organ will have no DNA of the person that it originally belonged to?"
] | [
false
] | null | [
"No, that's not how organ cell replacement works. ",
"As cells in a transplanted organ die, if they are replaced they're replaced by cell division within the donor organ.",
"Since all of the original cells contain the donor's DNA, so will the replacement cells. The new host's DNA is never incorporated the cell... | [
"Nine months is actually nowhere near the limit...",
"https://www.scientificamerican.com/article/fetal-cells-microchimerism/"
] | [
"Ngl that's pretty damn spooky.",
"For the rest of your life, you have someone else's DNA inside you. As opposed to the previous 9-month limit on having someone's DNA in you."
] |
[
"How do the antibodies in a blood donors blood behave in the blood recipients body?"
] | [
false
] | [deleted] | [
"They work just fine; this is basis of ",
"immunoglobulin therapy",
". However, they don't work very long; half-life of various immunoglobulins is only a few days.",
"What blocks the significant response from the recipient's immune system is that the recipient has to be immunosuppressed to receive a transplan... | [
"PhD here in a closely related topic. Your intuition is correct: the donor antibodies are simply too low in quantity to cause significant problems. ",
"A question on a more dangerous scenario is whether donated B and T cells specific to the ABO antigens can be encouraged to proliferate ( even hypermutate for B ce... | [
"Thanks for the response. I would be curious to know where that cutoff exists, I assume one cannot transplant healthy antibodies between individuals of compatible ABO and see an uptake of the immunity so I'm curious how the foreign bodies are signalled."
] |
[
"What happens if water is not permitted to expand when frozen?"
] | [
false
] | null | [
"There are other forms of ice which take up less volume than the ice we're most familiar with. These occur at high pressures. ",
"http://en.wikipedia.org/wiki/Ice#Phases"
] | [
"This happens:",
"http://www.youtube.com/watch?v=UlBFQCXdLXc&feature=youtube_gdata_player",
"Edit: For those who may doubt its authenticity, I've found a better video:\n",
"http://www.youtube.com/watch?v=erlZb8QiPkg&feature=youtube_gdata_player"
] | [
"Ice is not the only material to do this. Most solids have more than one phase. Material science delves deeply into control the phases of materials to obtain optimal properties. For exam a steel can have vastly different properties based on solely how it is cooled. ",
"This site",
" explains more about the proc... |
[
"If E=mc2 holds true then light has mass and if mass and time become infinite at the speed of light. How is lights mass not infinite?"
] | [
false
] | null | [
"E = mc",
" only applies to a particle that isn't moving."
] | [
"So the energy being measured is any other form of energy other that kenitic?"
] | [
"The energy that has a mass equivalence is the energy present even in a reference frame where the total momentum is zero. So in other words, it's the energy that is ",
" translational kinetic energy of the particle."
] |
[
"AskScience AMA Series: I'm Chiara Marletto - I'll tell you about a new way of formulating physical laws. I'm a quantum physicist and author of \"The Science of Can and Can't\". After this, you'll know the key to recasting the laws of physics to capture things like information, life and even the mind."
] | [
false
] | I'm Chiara Marletto and I am a physicist, with a passion for storytelling. I work on fundamental problems in physics, and I love quantum theory - one of the deepest and most fascinating explanations we have for physical reality. I have written a book to outline a radically different approach to expressing physical laws... | [
"I just liked writing a book on these new ideas - I love writing in general and it was natural to collect in a popular book some of the good informal explanations for this new theory I am exploring with my collaborators. I think the standard format of scientific publication is perfectly fine for communicating with ... | [
"I just liked writing a book on these new ideas - I love writing in general and it was natural to collect in a popular book some of the good informal explanations for this new theory I am exploring with my collaborators. I think the standard format of scientific publication is perfectly fine for communicating with ... | [
"The theory I am outlining is using the same well-known scientific method - but it's adopting a novel approach to expressing fundamental laws -- not in terms of trajectories and laws of motion like say Galileo and Newton did, but in terms of explanations about which tasks, or transformations, are possible and which... |
[
"Are there any creatures with a single type of cone in their eye?"
] | [
false
] | So we humans have 3 color receptors, a dog had 2, and insects like bees have 4. Is there anything with only 1 color receptor? | [
"Whales, dolphins, and sharks only have one type of cone receptor---probably there are not much advantage to color vision under water. Some mammals that are active at night also only have one type of cone, e.g. some kinds of bats, hamsters and monkeys.",
"Humans actually have four types of receptors: rods and thr... | [
"probably there are not much advantage to color vision under water.",
"Depends on where you live. Fish that live in shallow, clear waters often have four cone varieties. But for large predators, especially ones that hunt in deeper water, it's not as useful"
] | [
"Mantis shrimp?"
] |
[
"How do we know the number of stars in a galaxy?"
] | [
false
] | So I came across . It says that there are 800 billion stars in it. How do we know the number with any sort of accuracy when (I assume) the resolution of our telescopes is not good enough to count individual stars? | [
"They estimate....",
"Useful information includes:",
"\nTotal luminosity",
"\naverage luminosity per star. (After accounting for dust, and for average age of stars, which can be accounted for by measuring metalicity...) ",
"Size",
"\nShape",
"\nRotational speed profile (galactic mass) ",
"Suffice to... | [
"This is correct.",
"Counting stars isn't even an option - with the exception of the nearest handful of galaxies, we can't even see individual stars to count them."
] | [
"I'm not certain, but for example, they could measure the area of the Galaxy with the telescope, and then sample different areas to find an average star density (either from counting individual stars which is unlikely, or applying models of similar galaxies that they have already researched) and then calculating ho... |
[
"Computers are almost always performing more than one task at once. How do the computers keep these tasks from getting \"mixed up\" with each other?"
] | [
false
] | null | [
"This is one of the roles of the operating system. There are some complicated details, but the most important thing here is the concept of ",
"virtual memory",
". With virtual memory, the operating system can present to each process (program) what seems like a continuous block of memory and guarantees that this... | [
"Just to clarify, the OS doesn't tell the task when to switch, it tells the CPU (usually via an IRQ). The CPU responds to the IRQ and the OS returns [task swaps] to a different task to give it CPU time. It's not voluntary on the part of the task.",
"In most cases task swaps also occur on syscalls (asking the OS... | [
"From a program flow point of view syscalls are instantaneous function calls. You'd have to use other syscalls to realize the the systime is not zero [or that walltime != usertime]."
] |
[
"Can someone's upper body be paralyzed while there lower body is functional?"
] | [
false
] | null | [
"Yes, there can be a form of central spinal cord injury that leaves the legs working but arms paralised, most of the time it come with impairment of arms, but yes, someone can have \"reverse paraplegia\"",
"I have a friend who is a t1-t4 paraplegic, and out of curiosity we were looking up other levels of paralysi... | [
"Yes. We generally call this central cord syndrome and it is not uncommon particularly in the elderly with spinal stenosis who sustained a hyperextention neck injury. Often it is associated with no actual fractures but instead with ligamentous instability.",
"As usual Wikipedia is your friend here. ",
"http://e... | [
"Short answer is yes it is possible, but unlikely.",
"Paralysis is caused in most cases by neurological damage. This can occur in several places, but the stereotypical paralysis patient has had a spinal cord injury. If the spinal cord is completely severed, the result is total loss of feeling and movement below... |
[
"If photons have no mass, why can't they escape the gravity of a black hole?"
] | [
false
] | [deleted] | [
"This is a misconception about black holes. A better way to thinking about it is that every path you could take from inside the event horizon leads back inside the horizon because space curves in on itself."
] | [
"Photons have no mass, but they are still affected by gravity. This is one of the core results of general relativity."
] | [
"Because gravity isn't some force proportional to the masses of two objects, as you may have learned in high school. It's a consequence of spacetime being curved. And anything moving through a curved spacetime will follow curved paths, regardless of whether it's massless or not.",
"But wait, there's more! Not onl... |
[
"Why is it that when I get sleep deprived I get severely depressed? What evolutionary purpose is there for this?"
] | [
false
] | null | [
"Also, why do I often have a hard time falling asleep while sleep deprived?"
] | [
"Actually, one study showed that sleep deprivation led to decreased depressive symptoms in subjects ",
"(source)",
" ",
"and the wiki for sleep deprivation",
"Your situation may be based on your own personal sleep habits and/or potential sleep disorders, and less to do with any ancestral selective forces. "... | [
"It is well established that sleep deprivation can lead to mood disorders and depression: ",
"http://healthysleep.med.harvard.edu/need-sleep/whats-in-it-for-you/mood"
] |
[
"How common is it to replicate research within different scientific fields?"
] | [
false
] | I was inspired by this post: I work in psychology and I have never read a published attempt to strait up replicate someone else's research. As far as I know there is very little disincentive to publish research that can't be replicated in psychology (let the ripping on psychology as a science commence!). How common i... | [
"Oh man, the first thing that came to mind was ",
"this article",
". If you can't read it, tell me and I'll host the pdf somewhere for you.",
" Basically what happened is that Homme Hellinga, who was a big shot protein designer with a meteoric rise to fame and huge money flowing into his lab turned out to be... | [
"That gets kinda hairy. People do not directly call each other out in my field via publishing non-replicative studies. I could try to rationalize it, but honestly everyone is afraid of pissing off other people in the field due to the fact that it might come back to bite them in the ass. I've had to bite my tongu... | [
"http://care.diabetesjournals.org/content/17/2/152.abstract",
"They replicated basic calculus. Does this count?"
] |
[
"My hair is brown but my facial hair is red. Why?"
] | [
false
] | null | [
"bah, stumbled in here via ",
"r/all",
". my apologies."
] | [
"Off I go!"
] | [
"Please keep discussion:",
"Civil",
"On topic"
] |
[
"Why are most pain relievers also fever reducers?"
] | [
false
] | null | [
"The pain relievers available over the counter are either NSAIDs (like aspirin, ibuprofen, naproxen) or acetaminophen (aka paracetamol or Tylenol.) Both act in some way to reduce the effect of a group of enzymes called cyclooxygenases (COX) which are important in producing inflammation. NSAIDs inhibit COX all over,... | [
"In short it is because fever and pain are caused by the same substances acting in different locations and drugs such as ibuprofen and aspirin inhibit the enzymes that produce these substances. ",
"In slightly more detail, inflammation at the site of injuries is characterised by a complex cascade of events. The C... | [
"Why is that? Isnt the difference just that COX-2 is mainly limited to inflamed tissue? "
] |
[
"What defines sentience? Is there a way to test for it?"
] | [
false
] | I've always been curious to find the answer to this question. Is it some level of technology that must be attained? Is it some level of communication? Is it a knowledge of self? Some combination of the above? I suppose I'm just trying to determine where sentience begins and ends for humans, and for other species. E... | [
"So... everything that's an animal is sentient? Slugs are sentient? Wouldn't that make just about everything sentient that's alive?"
] | [
"We should expect sentience of some kind or another among all animals that are capable of modifying their behavior in response to stimuli in the short term, which is pretty much all animals. Because animals are capable of volitional movement, they are adapted to react to stimuli through feelings. The best argument ... | [
"Hrm... okay, so is it just the mirror test? or is it a wider spectrum? Does that mean that all of those animals are sentient?"
] |
[
"Why do humans scream when they're scared?"
] | [
false
] | Is it a defense mechanism, and if so what is it supposed to accomplish? | [
"Humans are an extremely social species, and presumably had a tendency to express emotions very clearly/vocally. Screaming quickly gets the attention of all nearby humans that could help, kind of like crying when in pain, etc."
] | [
"And many animals are naturally afraid of loud noises, including humans."
] | [
"GAH, FUCK!"
] |
[
"Can cancer \"evolve\" like bacteria to resist treatments if we use those treatments often enough?"
] | [
false
] | null | [
"Cancer can acquire resistance to treatment, such as developing T790M mutations in EGFR mutant lung cancers treated with tyrosine kinase inhibitors. As cancer is not spread between individuals, this acquired resistance occurs within a single patient, not within a population like with micro organisms.",
"Individua... | [
"This is true and also part of the reason treatments are more effective before they metastasize. If you only have a small bit of tumor, it's possible to eradicate it with chemotherapy relatively quickly, but if it's a large mass that has spread diffusely, it's more likely to have picked up resistant mutations. Then... | [
"Cancer doesn’t work and evolve like a virus would, so I would think not, but as it can work hereditarily, then there is a possibility that a stronger ‘version’ of the cancer will be passed down through the generations "
] |
[
"How is the change in magnetic field due to spatial variation different from from motional emf?"
] | [
false
] | Consider the case where a wire is moving in a magnetic field, the source of the magnetic field can either be the loop itself(rail) or an externally applied one (magnet). If the conductor where to move, the induced emf would simply be the change in flux, which simplifies to ε = -vBL for motional emf where the charges ex... | [
"I believe it's not. Fixing the conducting loop and moving the magnet, of fixing the magnet and moving the conducting loop are equivalent descriptions of the problem. This can easily be seen by moving into moving frames of reference either centered at the loop or at the magnet. Not considering any acceleration phas... | [
"This is almost purely mathematical. Magnetic flux is defined as B*S, if B is not a function of space (at least localy where your S is). If you want to get the equation you have provided, you just differentiate the magnetic flux over time according to the product rule.",
"",
"ε = -vBL",
"This isn't a correc... | [
"Same direction and magnitude, nothing changes.\nDifferent direction, you have to encode the dynamics of your system in B(r,t) or in S(r,t)"
] |
[
"Why some elements violate the octet rule? (I.e. H and He are stable with 2, Be is stable with 4, B with 6, and rows 3+ can have more than 8)"
] | [
false
] | [deleted] | [
"The octet rule is just a rule. The underlying reality is based on orbitals. Electrons form a sort of a \"standing wave\". Classically, an analogue is an orbit. The plain \"circular\" (ball) orbit is the ",
" orbital. That gives one quantum number (",
"), so at ",
" = 1, 2, 3 ... the electrons are on progress... | [
"So I get H, He, and rows 3+ but still don't get B or Be. If one can eat 14 then don't they get 20 not 6 and 4."
] | [
"Elements H - He have only one ",
" orbital. Elements Li - Be have two ",
" orbitals. Elements B - Ne have two ",
" orbitals and three ",
" orbitals. ",
" orbitals start appearing from Sc on (transition metals); they fit 10 electrons. The next type, ",
", fits 14 electrons. See ",
"this diagram",
".... |
[
"Is it possible to separate alcohol from an alcoholic beverage by freezing the mixture and be left with the unfrozen, nearly pure alcohol."
] | [
false
] | Ok, I have this bottle of Admiral Nelson rum that I keep in the freezer and when it freezes, only some of it actually turns solid leaving part of the stuff liquid. I am under the assumption that alcohol cannot freeze but I could be wrong about that. So is the stuff that is unfrozen more pure alcohol or is the alcohol t... | [
"Yes, traditionally some apple brandies were made this way (by letting hard cider freeze overnight in winter and then pouring off the alcohol). However, in America this actually counts as distilling, and is illegal."
] | [
"This is FUD. The amount of methanol present in undistilled cider is trivial, and freeze distilling only concentrates two- or three-fold. The only reason it's dangerous in regular distilling is that one particular segment of the distillate (the heads) is extremely high in methanol.",
"Besides, all the ethanol y... | [
"Alcohol can freeze, but only at much lower temps than the rest of the stuff in the drink. So you could technically make drinks stronger by freezing them and skimming off the liquid alcohol. And actually I think there's a beer company in Scotland or Ireland or something that makes insanely strong beer using this me... |
[
"I get why being in body temp water and weather is uncomfortable, but why is drinking water that's 98.6 degrees unpleasant?"
] | [
false
] | null | [
"I believe the answer is actually rather surprisingly simple.",
"When we drink a substance normally, there is the tactile sensation of the fluid, possible taste (assuming it isn't tasteless) and a temperaature sensation that we are used to. However, when drinking water that is our exact body temperature, the only... | [
"Of course he means Farenheit... You know that 98.6 F is significant, while 98.6 C is not, so why would you even bring it up?",
"And yeah, drinking warm water is extremely unpleasant, and personally, makes me feel sick if I drink it when I'm dehydrated or overexerted."
] | [
"The OP uses the phrase 'body temp.' Yes, she should have been specific, but in the context of the question, you're just being pedantic."
] |
[
"Orca Whale color scheme"
] | [
false
] | Why is it that orcas all have a very similiar color pattern? Dogs of the same breed may look similiar, but don't have the same spots. Every orca I've ever seen looks the same. | [
"Dogs have been selectively bred by humans specifically to look different from each other. People like variety, and exaggerate it in dogs. People haven't been breeding killer whales to all look really different, so they pretty much all look similar (in a broad sense). "
] | [
"Well...no. There's other things which can cause diversity in coloration within a species, too. But people tend to select for really diverse appearances."
] | [
"So if left on their own, all animals would like nearly identical?"
] |
[
"Is a medications expiry date related in anyway to its packaging method?"
] | [
false
] | I have a bunch of medications in pill and capsule form that come in blister packs. Would putting them in to bottles effect their efficacy in anyway? I'm going traveling and prefer hardier bottles to avoid crushing. | [
"It certainly can have an effect. If a medicine contains compounds that are air or water sensitive (i.e., they decompose over time under those conditions), then taking them all out and putting them into a bottle would decrease their effective lifetimes. Only your pharmacist could answer that question for certain.... | [
"Blister packs also protect the pill itself from moisture and mechanical damage. Coatings can do a great job protecting the active drug from your body (saliva, stomach acid, etc), while still being relatively fragile. This is particularly true for controlled release doses (rapid OR extended release). Personally I'd... | [
"https://www.reddit.com/r/askscience/wiki/sources"
] |
[
"From what sorts of materials would a rover need to be constructed in order to withstand the extreme pressure, temperature, and acidity found on the surface of Venus?"
] | [
false
] | Or whatever other environmental challenges you can think of. For a reasonable mission duration. [edit: let's say 90 days minimum] Assume a beefy budget but not unlimited. The laws of physics still apply so weight and method of deployment will factor in. What do you think? Edit: Some great responses; thanks! But I'm see... | [
"The key question is \"for how long?\""
] | [
"The pressure isn't an issue at all... We frequently deal with 600 atmospheres underwater. The problem is heat. You can't even use a glass camera lens at that temperature."
] | [
"Sure you can use some strong metal for the structure, but I really doubt our silicon/copper/tin/whatever based electronics could be shielded in such a way to work on a planet with a 740 degree C atmosphere. What cooling apparatus could we ever use? How would we power it even if we could develop one?",
"For ref... |
[
"Why doesn't all the Uranium in a sample decay at the same time?"
] | [
false
] | On the latest Cosmos episode, Dr. Tyson explained radioactive decay. He said that, in a sample of something that contained Uranium, the Uranium decays and eventually turns into lead. So, if you measure the amount of both, you can figure out how old the sample is. Hopefully, I at least understand that part correctly. My... | [
"Radioactive decay like this is something that, at this point, we believe is totally random on a single-atom basis. If we have a single radioactive atom, we have no way of knowing when it will decay. With enough radioactive material, though, the decaying process falls into a pattern, because the ",
" of an atom d... | [
"It's not that there are different \"starting points\" - but rather, the entire process of radioactive decay is probabilistic in nature. You cannot point to any one atom and say \"they will decay in 5 minutes\". There simply ",
" a fixed \"decay time\". All the figures you see - rate of decay, or half-life - are ... | [
"Ah, ok. That does make sense. I'm obviously not a chemist, but I just inferred from what I learned that constant rate of decay + same starting point => same decay point. So, just to make sure I understand this correctly, there's different starting points. The atoms don't all begin to decay at the same time, which ... |
[
"Why do large icicles appear ribbed?"
] | [
false
] | This doesn't seem to be true of all icicles, especially the smaller onee, but most of the large ones (30cm+) appear to have this ribbed affect. What's causing this? | [
"This paper",
" (open access) suggests it's a result of dissolved salt. In laboratory experiments, pure water icicles do not form ripples.",
"We don't understand very well what goes on near the fluid-solid interface in solidifying mixtures, but there are weird partially solid \"mushy layers\" that might have so... | [
"Pretty well summed up by the last sentence \"this elegant example of natural pattern formation remains theoretically unexplained.\" Interesting that someone has actually worked on this professionally though."
] | [
"Consider this a common sense explanation - with smaller icicle, a water drop can make it all the way to the bottom of the icicle before freezing, and then freeze there. With larger icicles, the water drop may freeze on the way to the bottom and thus create what you're referring to as a ripple."
] |
[
"Biologically speaking, what happens when you get your \"second wind?\""
] | [
false
] | null | [
"No one completely knows, but the leading theories are:"
] | [
"Interesting. I thought point one was a well accepted and demonstrated fact. Why hasn't anyone been able to prove that the body has switched to burning fats during a second wind?"
] | [
"If you are referring to the phenomenon experienced during intense exercise... The jury's still out. No one really knows (yet!)"
] |
[
"What exactly is an \"engine\" (software-wise)?"
] | [
false
] | null | [
"ITs a frame work. Simply put it handles some expected functions, and returns answers and solutions.",
" speaking it is everything that isn't an interface or decoration.",
"If you were to compare it to car analogy, its the chasis, transmission and engine. Later you add buttons/pedals/wheels/seats/bodywrok to ... | [
"I'd compare a software engine to the powertrain of a car: motor, transmission, driveshaft, wheels, i.e. everything the car needs to move. Software engines are active components, in the sense that they maintain their own internal state and data structures and perform some kind of complex data processing. This is ... | [
"It's vague definition that uses analogy from real world: ",
"Roughly speaking it's the part of the system that does the main work and is the core of the system. You could as well use terms kernel, core, main- etc. to describe it but there are very vague conventions that dictate what word is used. For example in ... |
[
"Can metals be broken/damaged due to the photoelectric effect?"
] | [
false
] | Hello, I was reading about the photoelectric effect. I was wondering if the frequency of the EMR was high enough to surpass the work function energy (the energy needed for the electrons to break free from the positive ion metal attraction). Since the electrons in the metal are able to escape. Is it possible for metal t... | [
"/u/spaghettiJesus",
"At energies much much higher than the work function, it is possible to induce structural damage. But around the work function it shouldn't happen. "
] | [
"I think you're making a slight mistake here. In the photoelectric effect phenomenon only electrons are ejected from the surface and as such matter is not lost from the metal.",
"In photoelectric effect the electrons are liberated from the surface of the metal and the excess energy supplied is converted used up t... | [
"The electrons liberated are 'free electrons' which are free to move in the lattice of the material. Their presence or lack of them doesn't change the integrity of the metal. ",
"EDIT: this is wrong. Refer to ",
"this comment"
] |
[
"On a molecular level, what makes something adhesive? E.g. tape, glue."
] | [
false
] | Follow-up: Are there any solids that won't be adhered to? Maybe only a theoretical substance? Also, what would be special about that substance's molecular structure? | [
"Van der Waals forces. It describes how two molecules when close enough attract to each other outside of ionic and covalency, that is, without a chemical reaction. It explains how gecko or house lizards can climb on almost any surface. ",
"So, theoretically, if there is a compound that is totally van der Waal pro... | [
"Just in case you didn't know, there are two types of stickiness, adhesive and cohesive. You asked about adhesive so I'll address that first.",
"The goal in making something adhesive is to maximize the intermolecular forces between the two substrates. To start off, you want a gigantic molecule, a polymer, which b... | [
"As has been mentioned, it's believed that the adhesive properties of certain materials is due to the inherent van der Waals' forces found between the material and the substrate being adhered to.",
"Stick proof frying pans are a good starting point in finding a perfectly non-stick substance. They are typically ma... |
[
"A journey to the center of the earth?"
] | [
false
] | null | [
"Hi ourpablo thank you for submitting to ",
"/r/Askscience",
".",
" Please add flair to your post. ",
"Your post will be removed permanently if flair is not added within one hour. You can flair this post by replying to this message with your flair choice. It must be an exact match to one of the follow... | [
"Can I ask why so many people are asking this question?"
] | [
"I really couldn't say why others have asked, perhaps they're curious?",
"I've never seen it posted before, the thought just popped through my head today and I figured I'd ask."
] |
[
"If you had an alloy of every metal, would it have properties from every metal?"
] | [
false
] | Maybe an odd question, but I feel like you guys could answer it. | [
"Alloys don't really approximate combining the properties of the constituents. For example, many alloys are harder or stronger than all of the component metals."
] | [
"Likely no. The properties of alloys are often quite different to the properties of the component metals, because those properties often are the result of the substance's crystal structure and introducing some dopant (like carbon in steel, say) can completely change the structure and therefore a property like stre... | [
"It is most likely impossible to make an alloy out of every metal possible. You could easy embed inclusions of every into an alloy, but you wouldn't be able to get a homogenous mixture on all the metal elements due to their varying properties (notably melting point).",
"Some metals are also incompatible with each... |
[
"What causes the aftertaste one gets when administered certain anesthetics and illicit IV drugs?"
] | [
false
] | I had an EGD last week and remembered a medical taste come into my mouth. Some IV users have reported experienced this "taste". What causes it, and why does it have the flavor it does? | [
"This happens frequently with IV medications. It seems to be especially common with prefilled saline syringes. ",
"The mechanism is that when certain volatile compounds enter a vein and get circulated, within a few seconds they pass through the lungs. The compounds evaporate into the lung airspace and are exhaled... | [
"Any source on that? I always figured it was because it got into your blood, and the blood passed through your tongue shortly after and got in that way."
] | [
"I haven't found the original study where I read this.",
"This article mentions it in passing",
", in the conclusions section.",
"We wouldn't expect blood inside your tongue to affect your sensations, because your taste buds point outward. If we inject dextrose, you don't taste sweetness. If we inject highly ... |
[
"If we were to send a man into space at 99.99% of the speed of light. Would the time dilation allow him to live long enough to reach distant stars?"
] | [
false
] | Time slows down the closer we get to the speed of light, so if somebody were to approach c, then wouldn't they in turn age slow enough to last a trip to say, Alpha Centauri? EDIT: Thanks for all the awesome responses you gais. From what I'm understanding from the discussions is that the faster the person on the rocket... | [
"That is correct. If a person is traveling at 0.9999c toward Alpha Centauri relative to Earth, then length contraction means they see the distance between Earth and Alpha Centauri as being about 0.062 light-years. Then they will experience only about 0.062 years, or around 22.5 days, before Alpha Centauri reaches t... | [
"Absolutely. A person traveling to Alpha Centauri from Earth at 99.99998% the speed of light relative to Earth would have the experience of Alpha Centauri rushing toward them (and Earth rushing away from them) at 99.99998% the speed of light for roughly 1 day before the star shot past them.",
"Of course, this ign... | [
"Well that's not too bad. It's only 7384 g more than a human can survive sustained for one minute."
] |
[
"How does suntan lotion protect someone from UV rays?"
] | [
false
] | I've always wondered this. Sunblock is just a cream. So how does it actually stop the rays of the sun? | [
"Inorganic ingredients like zinc oxide or titanium oxide reflect or scatter ultraviolet (UV) radiation. Organic ingredients like octyl methoxycinnamate (OMC) or oxybenzone absorb UV radiation, dissipating it as heat.\n",
"Source"
] | [
"Titanium and zinc oxides are wide bandgap semiconductors. They absorb light over their band gaps. Light smaller than the bandgap is not absorbed. Though scattering and other effects also exist. "
] | [
"Simply, the particles in the sunblock either absorb the UV radiation and/or reflect it, thus preventing your skin from absorbing the harmful radiation."
] |
[
"what are the large voltages described in particle accelerators measured against?"
] | [
false
] | in press releases from the LHC, proof of the higgs was demonstrated by evidence occurring at huge voltages. what potential differences are these particles being measured against? and we read claims of gigantic voltages made in reference to the overall power of particle accelerators. what source are these voltages measu... | [
"If you're referring to measurements in \"electron volts,\" that is a unit of energy equivalent to the energy gained by an electron dropping through a potential difference of one volt. The mass of particles is often described in electron volts per c",
" , but the c",
" is usually ignored and we say that the ele... | [
"In the LHC we have bunches that contain about 10",
" protons.",
"The bunch crossing rate (how often bunches of particles meet in interaction points) for the LHC is 40 MHz. We have 2808 bunches around the machine. ",
"At the interaction points the beams are squeezed to a size of a hair to allow more collision... | [
"In the LHC we have bunches that contain about 10",
" protons.",
"The bunch crossing rate (how often bunches of particles meet in interaction points) for the LHC is 40 MHz. We have 2808 bunches around the machine. ",
"At the interaction points the beams are squeezed to a size of a hair to allow more collision... |
[
"Why do we all have different voices?"
] | [
false
] | null | [
"We all have different bodies and brains. Differences in vocal cords, tongue, teeth, and lungs can affect speech, but the brain is the main part. The brain is why lots of people can do foreign accents or impressions but still have a natural speaking pattern separate from those. We pick up our unique way of speaking... | [
"That would be a stretch. It's more nature and nurture. Your physical characteristics will impact tonality and what not. You're upbringing will impact cadence, pronouncation, and other influences. Finally, your brain will make its own choices combining all this input into your own voice.",
"You can consciously in... | [
"So, the reason of our voices being different than each other is we actually choose our voices."
] |
[
"Why does rotational motion seem to cause an infinite force that has no origin?"
] | [
false
] | I am confused about how rotational motion applies forces to a system. Newton set forth a (non-practical) thought experiment of two globes being connected by a string, and both the globes and the string as a whole rotated in a perfect vacuum of space (to clarify: the globes would in this configuration trace a large circ... | [
"Maybe this will help you get thinking in the right direction:",
"In the example of the spinning balls connected by a string, the force that the balls exert on the string is only a reaction to the force that the string is exerting on the balls. Without the string the balls fly off in uniform motion right? So th... | [
"You can have an infinitely prolonged force if no energy is used. It takes no inherent energy to maintain a force, energy is only used if the force is acted on over a distance. ",
"For instance, you can make a similar analogy with a weight on the end of a string tied to the ceiling. The string pulls up on the ... | [
"Yes. Energy is force times distance (in direction of the force). If there is no relative motion, there is no energy exerted. Force does not intrinsically require energy."
] |
[
"Why do we need a launch system like the space shuttle to get to space?"
] | [
false
] | If a plane can travel hundreds or thousands of miles on it's fuel (depending on the plane), why can we not simply fly the short distance into space? (Yes... I understand the occupants need things like air, etc. I'm just asking why we need 'rockets' to get there). EDIT: Air is the answer, I meant for the people inside... | [
"Vehicles attempting to get into space require thrust to counteract the force of gravity constantly acting on them. Planes can't fly into space as they require the atmosphere to generate lift; there is less air the higher they fly so there would be a point on their ascent where there would not be enough lift to all... | [
"You've answered it yourself - air. Not only does an aircraft need air to be able to generate lift with its wings, it also needs air to combust its fuel within the engines, and air to generate thrust. Aircraft cannot function in a vacuum.",
"Rockets are used because they contain everything neccessary for combusti... | [
"I realized that once the other person answered, and I feel pretty stupid.",
"For what it's worth, I meant air for the occupants. But still... I feel dumb."
] |
[
"Are there any good examples of species who hit an evolutionary “fork” and further evolved separately into both predator and prey?"
] | [
false
] | That’s about it really. I’m asking if the evolutionary trend towards either predator or prey is set in stone. | [
"I’m asking if the evolutionary trend towards either predator or prey is set in stone.",
"No, definitely not.",
"It wouldn't be meaningful to say that. ",
".",
"For example, here's the family tree of the placental mammals.",
"- ",
"https://en.wikipedia.org/wiki/Evolution_of_mammals#Molecular_phyloge... | [
"You can pick any two species and they \"forked\" at some point. So in the technical sense, any predator/prey species you pick is an example. I don't think that's what you mean, I think you mean that the split was somewhat proximate. I have no idea what the most related a predator/prey species is, on the scale of t... | [
"For a more recent example, the cichlid fish in Lake Tanganyika all evolved from a single ancestor species over the past 10 million years. Herbivores, predators, detrivores, and more. ",
"(Other African lakes have had similar cichlid radiations but this is the most extreme example.) ",
"https://en.m.wikipedia.o... |
[
"Type of chemical bond between cooked rice sticking to ladle?"
] | [
false
] | i have one stupid question or childish question. i used a ladle to take rice. After taking rice from the vessel and you make it dry (as i feel i will wash the vessel in the morning). The next day if i wash, it is very hard to remove the dried rice from ladle. if i put in hot water for few minutes it is easy to wash it ... | [
"Adhesion can occur in a number of different manners, but in this case, you have what are called \"van der Waals interactions\" - when molecules get very close to each other, they tend to stick. In this case, the soft carbohydrates, etc. are close enough to the metal to stick.",
"When you add water, you are hydra... | [
"A water molecule is small and so it will interact with the glass very little, while a starch molecule is comparatively huge and will interact multiple times. It will also be entangled with other starch molecules which themselves are interacting multiple times..."
] | [
"Thanks for the answer. Is that van der Waals interactions is that much stronger. I learned for instance a water molecule sticks to the glass is due to the van der waals interaction and it is easy to break."
] |
[
"Why do the sea level records from an island in the baltic sea do not show a rise in the sea level over the last 60 yrs?"
] | [
false
] | Serious question, I know climate change and the melting oft the ice caps leads to a general rise of the sea level, please don't put me in a corner with people who doubt that fact. I came across records from the coast of the island Usedom today (was looking into something related for work) and it may be a stupid questio... | [
"In short: ",
"post-glacial rebound",
". ",
"Longer: A sea level record in a place is a measure of ",
"relative sea level as opposed to eustatic sea level",
", meaning that the observed change in average level of the ocean relative to a fixed point on land is the product of the rate at which sea level is ... | [
"Very nice answer. On the east coast of N America, Canada and Maine will have much longer to prepare for sea level rise because of glacial rebound while folks in Florida are dealing with it now."
] | [
"Florida is TOTALLY isostatically rebounding, just for a different reason from what ",
"/u/theprofessoro",
" described.",
"See ",
"this paper",
" for example. Some of the highest points in central Florida are former coastal dunes, higher than the ocean ever got at the time they were made. How did they get... |
[
"Is it possible for a propeller-driven plane to exceed the speed of sound?"
] | [
false
] | I've seen a few accounts of pilots claiming to have broken the sound barrier during dives in prop planes, but have seen no evidence of a plane designed to get much past mach .85 or so. Is there a reason for this, or is it simply that jet technology came along as we were approaching this milestone? | [
"A ",
"similar question",
" was asked a few days ago.",
"NACA research",
" in the 1940s suggested that this was feasible, but as you suggested, it was discarded in favor of jet propulsion, which is a much simpler approach to the problem.",
"The problem is that the profile of the blade required to sucessfu... | [
"so what your saying is that by having the plane behind the propeller you place the body of the plane right in the explosion part of the sonic boom, thus ripping it apart. Solvable with placing the propeller on the rear end of the plane. perhaps even two propellers, for stability."
] | [
"so what your saying is that by having the plane behind the propeller you place the body of the plane right in the explosion part of the sonic boom, thus ripping it apart. Solvable with placing the propeller on the rear end of the plane. perhaps even two propellers, for stability."
] |
[
"This piece of paper compressed in a hydraulic press makes a small explosion and changes form. What exactly is happening here?"
] | [
false
] | null | [
"It looks like what is happening there is that trapped air in the pockets of the paper get compressed, heat up, and eventually explode outward. In the process, all of the gases leave the paper, the fibre network collapses, and any water adsorbed onto the surface of the paper also evaporates (paper can hold onto qui... | [
"5 days ago",
"6 days ago"
] | [
"Oops. Sorry my bad! Just saw the video last night, new to me assumed new to everyone."
] |
[
"Does the mass trade of foods like fruits and vegetables between different areas change their soils and hydrology?"
] | [
false
] | So I had this thought while eating an imported cucumber from Spain today. Since it's grown in spanish soil, it absorbs nutrients and water from the local soil. When I consume it in Germany, the remains presumably don't make it back to Spain, but stay in Germany after making their way through the local sewage system and... | [
"Let's consider a few things.",
"First, many of the nutrients that a plant absorbs change in form. If a plant absorbs nitrates (for example), those are frequently turned into proteins for use by that cell.",
"Next, your body will actually use some of the nutrients that the plant provides when you eat it. You wi... | [
"I do remember reading somewhere that the export of vegetables dries out certain areas in some countries. So especially the exported water could increase drought problems, if I remember correctly."
] | [
"Keep in mind though that a lot of the actual biomass of the plant is essentially carbohydrates that are made out of carbon dioxide and water. The carbon dioxide comes from the air which is free to move around the world so that doesn't really factor in but I suppose the water The plant took out of the ground and us... |
[
"How does an Atomic Force Microscope work?"
] | [
false
] | And is it the finest resolution we have? Third-year physics student, don't be afraid to whip out the math. | [
"Finally, a question I have some authority to answer! First up, I'm a PhD candidate very close to submitting my thesis. I've basically been using the AFM to characterize proteins and diseased tissue.",
"So the most basic principle of an AFM is very simple - it's 'feeling' a surface using a tiny 'finger'. Much lik... | [
"I'm in a similar situation to MrsKytro. I'm a PhD candidate working with AFM. I'd like to add more about the mechanism of sensing, if I may. ",
"I use the gramophone analogy as well. The needle on the record looks like ",
"this",
". This is attached to piezoelectric actuators, which can take a voltage and tu... | [
"Isn't there a 'tapping' and 'hover' mode?"
] |
[
"Trapped organic matter becomes oil, natural gas, or coal. What decides which path a certain pool of matter takes?"
] | [
false
] | null | [
"The main element of control is the length of the carbon chains, and this will in turn be influenced by thermal/pressure history and molecular structure of the starting organic matter.",
"Thus, oceanic planctonic algae has a lot of waxes and relatively short (less than 15C) chains and usually breaks into oil and/... | [
"In addition to the source of the hydrocarbons, the conditions under which they are buried are a major factor in determining what they end up as.",
"The best type of coal is anthracite which has lots of carbon and very few volatiles/impurities. It is just like lower-quality coal only it has been subject to low-g... | [
"any good articles on this? I'm looking for a good post for ",
"/r/oil"
] |
[
"Do germs have a circadian rhythm?"
] | [
false
] | For example say the cold virus? If you get sick with cold in a timezone 12 hours away, do the cold symptoms follow local time? What happens when you return home? | [
"However there is a ton of research on the seasonality of viruses (influenza, varicella). Especially recently when concerning the gut microbiome",
"https://europepmc.org/abstract/med/218446",
"https://scholar.google.com/scholar?hl=en&as_sdt=0%2C33&q=virus+seasonality&btnG=#d=gs_qabs&u=%23p%3D-zybWEnZGAsJ",
"h... | [
"Germs are simple bacteria and viruses which don’t have a nervous system. without a nervous system you can’t have a circadian rhythm. ",
"bacteria and viruses don’t sleep or rest. they just kind of exist and move around taking in nutrients to divide. viruses definitely don’t rest or sleep because they aren’t even... | [
"I hadn't realized that. This is amazing, thank you."
] |
[
"A Question about Evolution and living in the modern age."
] | [
false
] | I'm not sure this question even makes sense, but I've had this thought on my mind lately and thought this might be a good place to discuss it. Evolution caused humans in different areas of the world to grow in different ways. You can look at most people and generally tell what area of the planet their ancestors come ... | [
"There is evidence that populations have genetically adapted to their environments. Tibetans, for example, have lower hemoglobin levels to counteract the high altitude they live in. Natives of Central Africa have a high frequency of the sickle cell allele, which is useful in combating malaria. ",
"It's a difficul... | [
"Strictly speaking, no we shouldnt live in places where our ancestors did not grow. ",
"Prime example for this is vitamin D.\nVitamin D requires exposure to Sun. White people live in the north = low exposure, therefore, their body has adapted such that they dont need as much sun to produce adaquate vitamin D.",
... | [
"an awesome free article: ",
"http://www.sciencedirect.com/science/article/pii/S096098220902065X",
"Your question makes sense, and the comment of zfishkiller is great. ",
"Consider the timeline graphic of evolution in the article; we humans began to diverge about 150 thousand years ago. Our species however ... |
[
"Would it be possible to drink a mixture of NaOH and HCl?"
] | [
false
] | Say you took 0.01M of each and poured each simultaneously down a funnel. In theory wouldn't you just get salty water? Would the funnel just have to be really long? Obviously I'm not going to be trying this any time soon, but my roommates and I were discussing this and I wanted to see what everyone else thought. | [
"Disclaimer: NEVER EVER TRY THIS",
"But yes, you'd just get salty water. There are chemistry teachers who have done this as a demonstration."
] | [
"Stomach acid is strong, actually, HCl is a strong acid. 0.5% doesn't mean it's weak, that's a pH of ",
" 0.87, assuming (incorrectly) that it is diluted in nothing but water."
] | [
"Seriously? You know what would happen if the titration was even slightly unquenched?"
] |
[
"What effect does isoelectric point have on protein migration in an SDS-PAGE gel?"
] | [
false
] | I have three proteins all of slightly, but distinguishable, different sizes. Two of them have come out as the same size? What can affect the migration through the gel? | [
"Postranslational modifications (phosphorylation, ubiquitination, sumolation, cleavage by a protease). Degradation when you heat it in sample buffer. Trying a different % gel or running it longer are probably the easiest things to try."
] | [
"Generally, the SDS masks any charges (because it confers a lot of negative charge itself), so unless your protein is really positive or negative, the effect should be negligible. Of course, you might just have some quality issues with your gel as well. Try changing the concentration of acrylamide (as resolution is... | [
"Forgot PTMs, good call."
] |
[
"Has anyone gotten their Masters and then gotten a PhD in another field? Could you provide me with some insight, please?"
] | [
false
] | null | [
"I think ",
"/r/askacademia",
" will be able to help you best."
] | [
"Try ",
"/r/AskAcademia",
" for best results. "
] | [
"Thanks. "
] |
[
"What are some usual methods for proving that a number is transcendental? Why is it so hard to prove that a given number is transcendental?"
] | [
false
] | null | [
"The argument still holds, because you do still need a proof for each particular number that it satisfies that property."
] | [
"The argument still holds, because you do still need a proof for each particular number that it satisfies that property."
] | [
"Essentially there is only one known method to show that a number is transcendental. Every proof has the following basic idea at its core. ",
"Assume the number is algebraic. Construct in a clever way an auxiliary number related to your original number. Use the algebraic assumption to show the auxiliary numbe... |
[
"At the atomic level, what determines the qualities of different metals?"
] | [
false
] | It's clear enough that the ability to form metallic bonds is responsible for the properties of metals vs nonmetals. Further it seems pretty clear that electronegativity/atomic radius determines that ability. But what makes, for instance, iron harder than copper? Why can I bend a lead bar with my bare hands but an iron ... | [
"The property of lead you're describing is due to its ductility and malleability (malleable being somewhat loosely defined). Hardness is also related to these two, per its normal definition as a material's resistance to local deformation. Several differences in materials can give rise to more or less ductility. ... | [
"This is all generally correct; I'm just elaborating.",
"Dislocations are the flaws in the crystal that permit deformation. If you base the strength of a metal based on the bonding energy between atoms you'll end up over estimating the strength of the material by about a factor of two. It takes much less energy t... | [
"What you're looking at doesn't address the actual mechanism of deformation. It's related, but not direct. \"Particle packing\" is governed mostly by atomic size and crystal structure. Lead is a larger atom, so it can pack less atoms into a given volume, that's all. ",
"Lead is malleable because it can move d... |
[
"Is there a medical condition where mammalian red blood cells retain their nuclei?"
] | [
false
] | And does it have any adverse effects? Does the body produce more cells to make up for the loss of effective transport capacity? | [
"kinda sorta. young nucleated red blood cells can be released into circulation when there is hemolysis. Production of blood is related to oxygen delivery. But nucleated red blood cells are usually larger so no loss of oxygen carrying capacity."
] | [
"Yes, many conditions cause this. When there is a greater need for red blood cells than ability to produce them, the bone marrow will eventually \"cut its losses\" and will start kicking out immature red blood cells. An occasional nucleated red blood cell is a normal finding on blood smear but an increased number o... | [
"I don't know if your curiosity is general enough for my answer to interest you, but here goes: Birds have nucleated RBCs.\nHere is a good source: In answering the question about why birds have nucleated RBCs, they answer as to why they think mammals don't. ",
"http://www.madsci.org/posts/archives/2000-04/955119... |
[
"Is it possible to control a nuclear explosion?"
] | [
false
] | I don't mean in terms of a bomb, but could you create some sort of chamber to control a nuclear explosion and focus all the energy in one direction creating a thrust, if this is possible could we apply it to space shuttle's creating "nitrus" for space shuttle? Control the explosion force all the energy in one direction... | [
"I don't mean in terms of a bomb, but could you create some sort of chamber to control a nuclear explosion and focus all the energy in one direction creating a thrust ...",
"Yes, this is possible, in fact there was a program to develop this kind of thruster (",
"Project Orion",
"). The only reason it's not be... | [
"Not necessarily. A properly designed booster would produce a long-lasting tolerable acceleration rather than a short, unbearable level of acceleration. If this failed, then the idea would have no merit for human space colonization.",
"Oh -- you meant in the even of an explosion? Well, perhaps, but you know, rele... | [
"what about if it launched off earth using regular fuel then kicked into its nuclear power at a safe distance from earth's atmosphere?"
] |
[
"Help write a sci-fi novel. You get to be Xing Mu Sheng. You play earth like a videogame from space. I'm Bai Bai Rou."
] | [
false
] | null | [
"Nice idea, but not in ",
"/r/AskScience",
" please."
] | [
"I wanted to ask scientists so it wasn't a bunch of laymen. Where do you suggest? I'll happily do it elsewhere."
] | [
"You'd get better writing from ",
"/r/writing",
", that's a nice place with a fair number of readers. Otherwise, try the space or astronomy reddits, since it's kinda space related. Or else ",
"/r/scifi",
" or ",
"/r/sciencefiction",
". Or just try ",
"/r/science",
", perhaps? I really don't know."
] |
[
"Could there hypothetically be two planets in the same orbit?"
] | [
false
] | [deleted] | [
"could another earth-sized object fit Into earths orbit and be stable?",
"No, there are no stable configurations where two planets could orbit in the same path. You could put the two planets on opposite sides of the Sun, and assuming they're all point masses and there are no outside forces and there are no pertur... | [
"It is more likely to find smaller bodies 60 degrees ahead or behind a planet in its orbit. This is where the so-called Trojan asteroids of Jupiter are found, and one of Earth's Trojans. The point exactly opposite is possible, but orbits here are unstable compared to the ones at 60 degrees.",
"Look up \"Lagrange ... | [
"I've actually heard of those, particularly with some asteroids in about the same orbit as earth. ",
"These asteroids are tiny compared to the earth though, could another earth-sized object fit Into earths orbit and be stable? "
] |
[
"How do they measure atomic radii? Or to be more broad, how do scientists work with super small things like atomic particles and protons and electrons, measure them, weigh them, etc.?"
] | [
false
] | I've been reading up on my old chemistry stuff (its the most basic of basic intro to chemistry courses, but I'm just curious). It dawned upon me, while I learned about trends in the periodic table (such as, decreasing from left to right or bottom to top), there is no mention of how the pioneers of chemistry came to fin... | [
"As for getting mass, that's much easier than you might think. If you have a thing and you push on it, F=ma (or F=dp/dt more specifically) you measure how it accelerates and you can tell what its mass is. Well one of the easiest ways of doing this is with charged particles you accelerate the particle with an electr... | [
"At least as my memory serves, the atomic radii are actually derived from the bond lengths observed in various types of solids & molecules (ionic and covalent compounds as well as metals). So, for example, you'd be interested in seeing the bond lengths sodium makes when in pure sodium metal as well as in sodium ch... | [
"Thank you. Much appreciated! This satisfies my curiosity. Its just one of those things that bothered me as I was reading since it never explicitly says how these values came about."
] |
[
"How do other great apes deal with finger and toenails?"
] | [
false
] | As a modern human, the longer our nails get the more of a nuisance they become. It feels as if longer nails inhibit fine dexterity, increase pain sensitivity of digits, and make digits more susceptible to injury under mechanical stress. This would presumably be true in the wild for ancient humans and modern great apes ... | [
"Great apes treat fingernails in different ways.",
"Some allow them to grow until they break off. Others bite them and some even use rough stones as natural fingernail files. Great apes in captivity often need some form of supplemental nail care.",
"Non-human primates often use their forelimbs for locomotion so... | [
"I'd expect a captive ape to be able to use a nail clipper after being shown what it does."
] | [
"They're pretty smart, but they also might hurt themselves or clevery use it as a tool for some unintended purpose. So it's all about safety rather than running the risk of what's possible."
] |
[
"If science says that the higher the gravity in a reference frame, the slower time runs in that frame compared to elsewhere, then can you use another force, like centrifugal force, to simulate gravity in a reference frame to slow down time?"
] | [
false
] | My thought is that because the passage of time related to gravity is based on different frames of reference, could you exert a force in this frame of reference that is indistinguishable from gravity, and thus slow down time? A force like centrifugal force could be identical to a human in a certain reference frame, but... | [
"Yes, this is exactly right! A key insight of general relativity is the so-called ",
"equivalence principle",
", which states that the effect of gravity is equivalent to that of being in an accelerating frame of reference. A uniformly rotating object undergoing centripetal acceleration fits this bill fully! So ... | [
"Yes. Its just the expected time dilation as from special relativity. Time passes slower for objects traveling at high speeds than for objects at lower speeds.",
"However whats more interesting and \"looks like\" gravitational time dilation is when you considers observers along various distances from the center o... | [
"Wait, so...theoretically, one of ",
"these",
" spinning at an extremely high speed could create a distortion in time?"
] |
[
"Why don't new singularities form in the extreme densities and temperatures within a black hole's event horizon?"
] | [
false
] | null | [
"I'm not sure exactly what the question is asking, but the event horizon isn't a physical thing or a thing at all. It's just the boundary region where gravitational forces exceed the speed of light; aka anything that goes through it has all future worldlines going towards the singularity. It has an extraordinarily ... | [
"If a singularity were to form in there, we wouldn't know. There is kind of an event horizon we can't see past."
] | [
"I realize the event horizon is only a mathematical boundary. What I'm talking about is how matter from the accretion disk behaves as it falls through the event horizon and towards the central singularity. Based on ",
"this clip",
", any infalling material becomes incredibly energized. I'm asking why this super... |
[
"Near Death Experiences?"
] | [
false
] | I've been thinking about near death experiences lately.. my mother is a firm believer and tries to get me to read books by people who have died and come back.. I've heard that there are scientific explanations for the "white light" people see and stuff like that.. anyone able to explain it to me? People come back from ... | [
"Your brain can start to do some really bizarre things when your homeostasis is disrupted. This includes hallucinations, stereotyped behavior, out of body experiences, etc. ",
"There is a bizarre phenomenon you get when someone gets really bad ",
"hypothermia",
" in which they will start undressing and burrow... | [
"Oh completely non-credible. I was meaning to point out Michael Shermer's contribution, as it has a very good explanation of the scientific basis of near death experience. I certainly didn't mean to imply that Deepak Chopra has anything useful to say on the subject."
] | [
"I've had a 'near-death experience' after I accidentally cut myself quite badly, came back in the house and passed out; from my perspective I suddenly found myself standing in a bright white environment and I was aware of some people talking about me but I couldn't speak and I had no memory of how I got there. I b... |
[
"How does pure energy interact to form matter?"
] | [
false
] | null | [
"Damn you Mr. Spock! Damn you for introducing the conceptual fallacy of \"pure energy\" into popular culture!",
"The issue here is that energy isn't a \"thing,\" it's a property. Things ",
" energy just like they (may) have mass, length, volume, momentum, etc. Rather than reading E=mc",
" to say that mass ... | [
"then why does mine overheat?"
] | [
"Well, energy has to take some form, i.e. kinetic, the energy of a photon, etc., so \"pure energy\" isn't really the best-defined concept. It's not like energy (well, apart from the possibly nonzero vacuum energy) just \"floats\" around the universe. That being said, a good example of what I think you're trying to ... |
[
"How are Neanderthals a different species from Homosapiens if they could produce viable offspring together?"
] | [
false
] | null | [
" some scientists consider both different species, others do not. The biological species concept is a human-made concept and there are a lot of grey areas.",
"\nWhat is a species?\nTaxonomists argue all the time about what exactly a species is.\nThe general idea of a species, as I was taught in high school, is a ... | [
" Different species can certainly produce viable offspring. This is covered in ",
"Why can two different species sometimes hybridize and produce viable offspring? Shouldn't they be the same species?",
". Interbreeding between different species is not unusual; there are many unambiguous examples. Even horses a... | [
"Yes, but because the species concept is so well, vague, people like to believe what is more convenient for them and I can't really blame them. One example that comes to mind is the yellow wagtail.. One species with a lot of regional variation or a lot of different species? Some organisations count them as seperate... |
[
"NASA release of close-up Pluto images livestream at 3pm EST"
] | [
false
] | null | [
"\"Charon is [geo] active\" - Alan Stern ",
"Image of Hydra! ",
"http://i.imgur.com/FN4BLu7.png",
" ",
"Methane on Pluto! ",
"http://i.imgur.com/fkQELTJ.png",
" ",
"Charon close up! ",
"http://i.imgur.com/SVhOSjj.png",
" ",
": ",
"http://i.imgur.com/meaqdRP.png",
" (no craters!?)",
"P... | [
"To think... such high resolution photographs of an object 3 billion miles away. These images are stunning."
] | [
"They were throwing around three possible explanations during the press conference, ",
"Sufficient radioactive material generating heat. ",
"Some sort of internal phase change, like the freezing of an underground ocean. ",
"Some unknown mechanism which allowed Pluto to retain its heat of formation better t... |
[
"If the major event that triggered the extinction of the dinosaurs never happened, could they have evolved to our level of intelligence?"
] | [
false
] | null | [
"That is in fact one of the biggest puzzles in the speculation about extraterrestial life. For us humans, being intelligent seems to be a pretty neat trick in the survival of the fittest. So why is everything else so dumb? As far as we know, we are the only intelligent civilized species in the history of life on ea... | [
"You seem to be missing something like",
"d) Intelligence is both a particularly useful and difficult to evolve trait, like flight. In the history of life on this planet, flight appears to have evolved independently only 4 times yet those animal groups which evolved flight are mostly extremely successful (except ... | [
"<IAMNOTASCIENTIST>",
"Time doesn't necessarily equal intelligence. For instance the alligator has been around for about 200 million years, about the same amount of time as mammals. For a really stark example, jellyfish have been around for about 500 million years.",
"Intelligence seems to be a chance occurrenc... |
[
"How much does at-home recycling actually help the environment? I have heard the actual benefit is pretty much nil, is this true?"
] | [
false
] | null | [
"If you did not burn the paper for heat you would have to get the energy some other way. In most jurisdictions that means fossil fuels. Incineration can actually be an incredibly green way to acquire energy from waste, as long as the incinerator is properly constructed and filtered.",
"There are even better thing... | [
"I'm a recycle truck driver for a waste company. We currently single stream our recycle (meaning everything dumped together) using sideloaders.",
"This process is extremely efficient and only exists to get people to recycle more and reduce the cost to the consumers. However the downside is cross contamination. I ... | [
"To add, if paper is decomposed by fungus (fungus are responsible for most plant matter decay because they're better at breaking apart cellulose) the CO2 is likewise directed into the atmosphere. When the carbon is sequestered with filters, we can prevent this.",
"This is why growing forests isn't a long term sol... |
[
"What is the current scientific opinion on how the internet influences our minds/brains?"
] | [
false
] | Colloquially, there is a trend to say that the internet has had a detrimental affect not only on social interaction but also on the way in which people learn and retain information. But with developments like Google the pressure to remember things is no longer there. Would that imply that now our brains are being geare... | [
"You may be thinking of ",
"this Science article",
", which reports:",
"This is preliminary evidence that when people expect information to remain continuously available (such as we expect with Internet access), they are more likely to remember where to find it than to remember the details of the item. One co... | [
"Like outsourcing memory.",
"Would this free up that part of the brain for other uses?"
] | [
"I remember reading an article where the author posited that the gigantic wealth of instant-access information is making us shift from long-term, single topic attention to short-term, multi-topic attention. That is, where before information would be absorbed by reading articles and books, now we can obtain informat... |
[
"How does a stem cell know what body part to become naturally?"
] | [
false
] | What type of communication happens inside an embryo? What prevents, lets say, multiple livers from forming? Is there some sort of identification process that happens so a cell knows "okay those guys are becoming the liver, so I'll start forming the lungs" ? | [
"The process you're referring to is called \"Differentiation\", which in biology refers to stem cells becoming other cell types.",
"Chemically: The chemical properties of the surrounding the cell and available nutrients play a factor. These are things like pH, oxygen levels, CO2 levels etc.",
"Physically: Cert... | [
"The chemicals surrounding certain stem cells determine what it develops into. Think of it like parenting: different methods of parenting will raise different children, depending on how the child was raised and what the parents did to it."
] | [
"In addition to chemical stimuli, it has been revealed that the mechanical stresses and forces also play a role in differentiation. "
] |
[
"Can you laser etch a hollow tube in glass?"
] | [
false
] | Is it possible? | [
"This is actually done by laser sometime, when something special is needed. But yes, drawing capillaries is way easier. Were you thinkign of something specific. "
] | [
"Yes, \nI was thinking about making a \"passive solar tracking\" glass.\nFilling the glass infront of a solar cell with a bunch of tubes facing many directions acting like tiny fiber optic cables.",
"Have all the ends come down perpendicularly on the cells, to ensure direct sunlight from any angle, so power produ... | [
"You could but it is easier to draw a hollow tube down into a capillary. It is just a matter of picking the right laser for the glass system"
] |
[
"On a clear night, why do some stars twinkle more than others that appear to be of similar size?"
] | [
false
] | I understand that size is relative to our perception, but still. | [
"I don't think the time scales for stellar and interstellar processes are right to explain twinkling."
] | [
"I assume by size you mean brightness. Bright stars do appear to twinkle more than dim stars.",
"But there are a couple of things that may make one star appear to twinkle more than another of the same brightness. If it's lower in the sky, its light is passing through more atmosphere so it will twinkle more. And i... | [
"Twinkling (technically called scintillation) is the apparent change in brightness, colour, or even position of a distant and luminous object as viewed through a medium. In our case we're talking about terrestrial scintillation and the medium is our atmosphere. On the whole terrestrial scintillation effects are cau... |
[
"Particle physicists of reddit. How does one detect and characterise the many different types of fundamental particles?"
] | [
false
] | I'm a chemistry student, so this baffles me. | [
"There's been lots of different methods used over the last century or so. It depends on the lifetime of the particle, its mass and charge, the technology available at the time, etc. Most of them work by either directly detecting either ",
"scintillation",
" or ionization. Basically, as a particle passes thro... | [
"The fundamental thing that allows us to detect subatomic particles is the process of ionization. When an energetic electron/proton/photon/etc comes into contact with an atom, and interacts, it knocks electrons away from the atom. Based on what we do with those electrons, we can figure out the rest.",
"For inst... | [
"For reference, see the cross-sectional picture of the atlas experiment (at the LHC) here:\n",
"http://atlas.ch/photos/events-general-detection.html",
"In high energy physics, once particles are produced at the collision, here is what we do to identify particles:",
"We use a \"tracker\" to precisely determine... |
[
"Will cryogenically frozen people ever wake up?"
] | [
false
] | Is the practice of cryonics (freezing a terminally ill patient in hopes that medicine will one day be able to wake them up) in any way legitimate? Has the process of freezing a person irreparably damaged cells? | [
"You might look at the ",
"FAQ at Alcor",
", and the ",
"FAQ for scientists",
" at the same source.",
"They don't freeze people these days: the process used is vitrification, which minimizes ice crystal formation when performed under ideal circumstances. Fine structure in the brain is preserved. The same ... | [
"If something is frozen fast enough, the ice crystals will not have time to grow large enough to pierce cell walls. This is why we are able to \"flash freeze\" foods without them turning into mush."
] | [
"Source?"
] |
[
"Most AI research seems to look to neurology as the answer. What do Neurologists think of the chance of their field producing methods for making an AI?"
] | [
false
] | null | [
"Most AI research seems to look to neurology as the answer. ",
"From the machine learning side of the fence, this is really not true.",
"Some proportion of methods were inspired by biology, but that's about it. Not many people (I can't think of any) are relying on Neurologists to crack AI for them."
] | [
"Ah right sorry if thats wrong. It was just the impression I got.",
"How do you rate the chances at the moment?"
] | [
"It's inevitable. Human's are just complicated machines, and if we keep working on it we will get there eventually.",
"I can't say when we will get there, or if human-level AI's will be more useful/cost effective than just relying on humans. I imagine they'll be good for something, but it's still an open question... |
[
"If you were to put 10 box fans in a straight line all facing the same direction (like dominoes); would the air coming out of the last fan be stronger than a single box fan?"
] | [
false
] | I know there are probably a lot of variables to deal with here but I'm not sure what they are. | [
"Sure, each box fan causes a pressure drop from one side to the other. The magnitude of this drop is roughly related to how much kinetic energy is imparted on the air (i.e. how fast it ends up going). 10 box fans won't cause 10 times the pressure drop of a single fan but it will certainly be fore than a single fan.... | [
"Each added fan will increase the airflow a little less than the previous one did, until you reach a limit (which depends on fan size, speed, strength, angle, and structure as well as the fluid friction of air, interference from surrounding air etc.)."
] | [
"Don't forget the fan clocking. How the fans interact with one another can greatly affect the net flowrate. If the fan blades at row N+1 is clocked such that it stagnates the air from blades from row N, you're going to get diminishing returns really, really fast."
] |
[
"Is there any intuitive way to visualize the symmetries of the standard model?"
] | [
false
] | U(1), SO(2), SU(3), SO(3,1), i keep seeing these again and again when trying to learn about physics, but I have no idea of how to picture these visually as anything other than a bunch of matricies that I don't understand because I don't have a way to picture them. is there any sort of intuitive way to understand then? | [
"Do you want to visualise their action or the manifold of the Lie group?",
"U(1) is the group rotations in the complex plane, its manifold is a circle. SO(2) is the group of rotations in the real plane, so it is isomorphic to U(1).",
"I guess you meant SU(2), not SO(2)? SU(2) is the group relating all physicall... | [
"I made a ",
"comment",
" explaining how the U(1) gauge group gives rise to electromagnetic fields and charges a while ago. Basically, each point in spacetime has a copy of the group and they're connected to the groups of the nearby points. All the different ways you can put coordinates on these groups gives yo... | [
"how do these shapes and rotations correspend to real-world phenomenon though?"
] |
[
"Why do humans or many animal species get life long relationships?"
] | [
false
] | So I assume that if animals could spread their seed more they would have a better chance of having descendants. However with a life long partner you can't really do that. Why do so many creatures do this? What advantages are there aside from being able to raise and care/ensure the lifespan of your offspring. | [
"Animals with a long gestation period have much more vested in the survival of one offspring. ",
"It's funny because there are reptiles, mammals, even birds and all sorts of other animals that mate for life. ",
"Any insects? I mean, apart from spiders that eat their partners. "
] | [
"Thats the crux man, to ensure better survival of your offspring and your family it is better to be a tight unit, thus ensuring the genes get passed on. If you just dump em off and bail then you better have loads, or have super self sufficient offspring right away."
] | [
"The men or the women?"
] |
[
"Do the brains of those with mental illnesses demonstrate any differences with “normal” brains?"
] | [
false
] | null | [
"Yes there are neural correlates and markers of various mental illnesses... Do you have a more specific question? It's hard to answer this question generally. Is there a particular illness you have in mind?"
] | [
"I️ am interested in depression. "
] | [
"Then I recommend making a new, more specific post along the lines of \"what are the neural correlates of depression\" or \"are there physical differences in the brain of individuals with depression\". However, first I recommend doing a simple Google search -- there is plenty of information available"
] |
[
"Are Wood Peckers ever subject to brain damage? Do they suffer mini-concussions or have they evolved to withstand constant beating on trees?"
] | [
false
] | I was just curious about how wood peckers can constantly go throughout their life pecking at bark and hollowing pieces of trees out. I would imagine that beating my face on hard bark most of the time would cause either extreme headaches or brain damage. | [
"First, a woodpecker’s skull is built to absorb shock and minimize damage. The bone that surrounds the brain is thick and spongy, and loaded with trabeculae, microscopic beam-like bits of bone that form a tightly woven “mesh” for support and protection. This spongy bone is unevenly distributed in woodpeckers, and i... | [
"is this the same way sports helmets such as football are designed?"
] | [
"Roughly speaking, yes, but we can't achieve the same level of protection because a helmet protects the ",
" whereas a woodpecker protects its ",
". ",
"Helmets (I'm speaking motorcycle since that's what I know) are made of an outer shell to withstand punctures and abrasion and to spread the impact over a lar... |
[
"What would happen and what would I feel, if I was exposed to a temperature near absolute zero?"
] | [
false
] | null | [
"then the specific heat capacity and the mass of the object will determine the outcome.",
"Specific heat is part of it, but thermal conductivity (specifically, the contact conductance/resistance of the interface) plays a major role as well. If the conductance is very low then it doesn't matter if the SHC is high.... | [
"then the specific heat capacity and the mass of the object will determine the outcome.",
"Specific heat is part of it, but thermal conductivity (specifically, the contact conductance/resistance of the interface) plays a major role as well. If the conductance is very low then it doesn't matter if the SHC is high.... | [
"Just thought I would mention that the emmissivity of human skin does come into play here. While a vacuum would preclude conduction and convection, radiation would still rapidly carry heat away from the body. "
] |
[
"Why do people pause their conversations, when in small groups, when they walk past other people?"
] | [
false
] | null | [
"As an act of discretion. Often times you care not to share a private conversation with strangers."
] | [
"The issue I find with this thought is that they show no concern the second I am removed from their peripheral vision and speak at the same level of volume. I haven't seen the same level of discretion when two people are conversing while walking behind strangers or in front of them, while still speaking at a volume... | [
"Maybe it's a face to face thing."
] |
[
"If bacteria is everywhere and can seemingly grow on anything, then why aren't more colonies visible?"
] | [
false
] | Was just wondering since bacteria are on everything; handles/doorknobs, counter tops, floors, soil, underground, lakes/rivers, etc. I mean, we've all seen colonies in our toilets every so often as gross spots that seemingly double in size after a day or two, but seeing as how there are literally trillions in every roo... | [
"You don't see them because there isn't enough nutrient density for them to grow into visible colonies. Take a door handle made of metal. Sure there's bacteria there, but there's just not enough biologically available material present to sustain continual growth/division. Most bacteria are not actively dividing, th... | [
"Worth noting that things made of metal usually have very, very, very minimal number so of batcteria living on them as metals are either actively antiseptic or greatly inhibit cell growth ."
] | [
"I don't believe so. Ceramics are very inert so aren't in any way toxic to bacteria. Bathrooms are \"cleaner\" than kitchens because people are mostly a little more paranoid about keeping their bathroom clean. Plus there is very little in the way of food in a bathroom. Moulds that damp environments tend to thrive b... |
[
"Does the energy required to heat water increase as the water temperature increases?"
] | [
false
] | First time poster. Sorry if this should have been a physics question. If I had water that was 10 degrees Celsius, and I wanted to raise it to 20 degrees Celsius it would require the same amount of energy in joules to do so every time correct? So if I wanted to take that same water and raise it from 20C to 30C, would it... | [
"Thank you for answering my question in a laymans terms. "
] | [
"Thank you for answering my question in a laymans terms. "
] | [
"The amount of energy is constant but the rate of transferring heat energy is based on the temperature difference and the materials, for your design I would recommend an often water cycling and set the heat to a comfortable temperature than cycle a very hot water but with lower frequency. "
] |
[
"Why do so many people find rain relaxing?"
] | [
false
] | as title. | [
"I'm sure there is more to it, including what has already been posted here, but another consideration is the similarity to white noise. There are technical distinctions between the sound of falling rain and true white noise, but the psychological impact of any consistent and familiar background noise is bound to b... | [
"All of our terrestrial ancestors, including ourselves and all other terrestrial lifeforms, are utterly dependent on it for our survival. I figure we find it soothing for the same sorts of reasons why sugar is sweet, rotting meat is revolting and light is associated with good. Deep, evolutionary reasons."
] | [
"Part of it is certainly that sunlight (especially blue light from early morning and most of the day) produces serotonin which makes you more alert and more happy. Whereas darker weather, like during the rain, produces melatonin, which relaxes you and makes you sleepy.",
"There are also studies which support va... |
[
"What happens to the human body right after an extreme impact to the head, e.g., hockey and football hits?"
] | [
false
] | I was watching the clip of Nathan Horton from the Bruins getting blind sided by another hockey player from last night's hockey game. As soon as he hit, it seemed like he was just blankly staring and panting, but what made me cringe is the way his arm settled. It seemed like his arm just kind of tensed and then slowly... | [
"What you saw was a good example of the fencing response, which is typical in head trauma:",
"http://en.wikipedia.org/wiki/Fencing_response"
] | [
"Spot on! Thanks!"
] | [
"Now I really want to find a new born baby to try out the ",
"asymmetric tonic neck reflex",
" and ",
"tonic labyrinthine reflex",
"."
] |
[
"Why are gravitational and inertial mass equivalent?"
] | [
false
] | My understanding was based loosely on robotrollcall's explanation: that gravitational mass of an object tells space how to bend, and that bending tells the object how to move - or in the case of inertia, how to resist moving. So, say the object is sitting at rest in its own gravitational well from its own frame of refe... | [
"Why then is the graviton posited to exist?"
] | [
"They're equivalent because gravity is a fictional force. It's like centrifugal force - it ",
" to exist, but it's not really a \"force\" in the normal sense. Inertial mass is the tendency for an object to keep going in one direction. If you tie an object to a rope and swing it in circles, its inertial mass will ... | [
"That's a property of the universe we live in. There's no really better answer than that to a \"why\" question. If you disagree, give me an example of a fundamental physical phenomenon for which there is a satisfying answer as to \"why.\"",
"However, if you want to search for a more fundamental phenomenon that le... |
[
"Why does your body flip out when you dream about falling or slipping on ice?"
] | [
false
] | My understanding is that your muscles are supposed to be relaxed during REM sleep to the point where they can't really move, but occasionally I wake myself up when dreaming because my legs randomly flail about after falling or slipping in the dream. How is that possible? | [
"The same reasons you awake when you are shaken from the outside: your brain keeps a watch on the external world for protection. If you begin to experience hallucinations (\"dreams\") during hypnagogia, what is left of your conscious self integrates these as possibly real, so you wake up. A similar (but different) ... | [
"Hypnic jerk is the name you are looking for."
] | [
"Hypnic jerk is the name you are looking for."
] |
[
"What are the advantages and disadvantages of substituting sugar with agave syrup/nectar?"
] | [
false
] | There seems to be a lot of controversy, some people saying it is still a good substitute for sugar, others saying it is worse than using sugar. | [
"Agave nectar can be almost pure fructose, so substituting it for sugar in large quantities is not a good idea."
] | [
"Ah, I just posted a comment ",
"in the other subthread",
".",
"About glucose: it can easily be metabolized in vast quantities. When you eat bread, pasta, potatoes, stuff like that where the carbohydrate is present as starches, it's eventually broken down to pure glucose and that's how it's taken up by tissue... | [
"I'm wondering if you could elaborate a little.",
"The part that is unclear to me is how the body is affected by high levels of sucrose vs high levels of fructose. I found the ",
"wikipedia",
" explanation but it's a little vague.",
"On one side, agave nectar can be used in lower amounts (because it is swee... |
[
"Why do certain parts of our body reproduce themselves when destroyed (eg skin) and others don't?"
] | [
false
] | [deleted] | [
"Some parts of our body contain cellular machinery to heal wounds, and some do not.",
"In the skin, if you have a deep cut, the stem cells (basal keratinocytes) in the stratum basale need to divide and reform into a single layer to start regenerating skin cells in the epidermal layer above them. If they are too ... | [
"Cell signaling, but the entire process isn't completely understood.",
"Essentially hepatocytes are quiescent in G0 growth phase until they get a signal through p75 receptors to start growing again. They'll grow until they receive another signal (or lose the original p75 signal) to once again enter the G0 phase.... | [
"How come the liver cells do not over profilerate ?"
] |
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