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Saturday, February 4, 2017

Do NSAIDs (Paracetamol, etc...) slow down recovery from infections?

Do NSAIDs (Paracetamol, etc...) slow down recovery from infections?


Do NSAIDs (Paracetamol, etc...) slow down recovery from infections?

Posted: 04 Feb 2017 04:39 AM PST

NSAIDs (paracetamol, ibuprofen and others) can be used to reduce fever and inflammation. But as I understood it, fever and inflammation are mechanisms the body uses to boost the effectiveness of the immune system. Does the use of NSAIDs therefore reduce the effectiveness of the immune system in combatting an infection? If so, has this effect been quantified (e.g. "on average recovery time for infection X is Y% longer with a daily dose of Z")?

And is there any effect when NSAIDs are used when there is no infection (wounds, headaches, etc...)?

submitted by /u/Rannasha
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How can I estimate radiation exposure to x-rays in my practice?

Posted: 04 Feb 2017 12:57 AM PST

I'm a veterinarian that has to do a lot of x-rays, and usually the owners hold the animals. Most owners have no clue (I still get asked daily if they have to turn off their mobiles), but some are interested in knowing more about risks. I know that holding an animal for x-ray just once results in very little exposure to radiation, but just how little? Knowing the kV and mAs and the distance from the main focus, can I provide a good enough estimate of exposure? Thank you!

submitted by /u/firstcaress
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Why can our brain automatically calculate how fast we need to throw a football to a running receiver, but it takes thinking and time when we do it on paper?

Posted: 02 Feb 2017 06:09 PM PST

I was playing some catch the other day with a friend of mine. He would run off down the field, and I would throw the ball, and 90% of the time it was an accurate throw to him. The other 10% was due to wind difference, so I would adjust the throw and make it to him. All of that is done automatically in our brains, and it works pretty fast.

Now, why is it that when we see the same situation, but on paper, it takes time to calculate all of that information. Is it because our brains see the actual numbers compared to real world events that are happening right there? Or shouldn't our brain be able to pick that information and automatically translate it, as if it were happening right there?

Edit: fixed wording. But man, this blew up, and got a lot of great responses for this. Initially had it marked as physics, but I see it got changed to psychology. Very interesting. Thanks for all that took time, and made the explanation better for me!

submitted by /u/maxxxl
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How is actual sleep different from "sleeping" via anesthesia?

Posted: 03 Feb 2017 01:02 PM PST

What goes on in squirrel nests?

Posted: 04 Feb 2017 07:01 AM PST

A bit of context. I live in Eastern Canada, and grey squirrels (Sciurus carolinensis) are everywhere. They build conspicuous "nests" made of twigs and leaves, up in the canopy of trees.

Naïvely, I accepted what I was told as a child, namely that those are where squirrels retire to hibernate for the winter...

But here's the thing: not only do the nests seem a bit too small and flimsy to shelter the squirrels in any meaningful way in -30°C weather and winter winds, but the critters are scampering outside all winter long. So they manifestly don't hibernate. What exactly do squirrels actually do with those structures?

submitted by /u/Gargatua13013
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Why does the ISS need to "re-boost" in order to stay in orbit?

Posted: 03 Feb 2017 08:05 PM PST

The main common justification for this re-boosting I've heard is that since it is in low orbit, it is constantly falling a little bit and if it was farther away from earth it wouldn't need this. However, I just took my first physics course and we learned the equation for Centripetal Force is mv2/r, so from my understanding of this equation, why doesn't it just speed up in general in order to maintain a constant orbit.

submitted by /u/Tman1677
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Has a particle physics result that reached 3-sigma subsequently not reached 5-sigma and been abandoned?

Posted: 03 Feb 2017 08:22 AM PST

Famously, the higgs boson result was confirmed when the chances that the higgs finding was not real was no more than 1 in a very large number (5-sigma). Recent news articles on CP violation have reached 3-sigma. Has there been a promising result that got to 3 or 4 sigma, only to never get to 5-sigma significance?

submitted by /u/PrivateFrank
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What is the weak nuclear force?

Posted: 03 Feb 2017 02:59 PM PST

Whenever i hear about the 4 fundamental forces, i always hear 3 of them explained very to fairly well, and then we get to the weak nuclear force and whoever is explaining mumbles something about radiation and quickly moves on.

So, reddit, what is the weak nuclear force, and what does it do?

submitted by /u/bizzehdee
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What are the surface properties of a cooling dwarf star?

Posted: 03 Feb 2017 04:09 PM PST

when a star (like ours) dies it expands and collapses again

after collapsing it should still be pretty hot but its not heavy enough to become a black hole so it will become a dwarf star the dwarf star should be pretty hot and dense but heat keeps radiating away so my question is: when it cools down (after a long time) it should become cooler, so what would the surface of that dwarf star be like if the surface had ~200°C (solid? liquid?)

and if it cooled down even more to about 20°C could you just walk on it or will it never be solid in any way

submitted by /u/Taetares
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Is it purely coincidence that the human sleep cycle roughly matches the day and night cycle of Earth or is it the time of day that determined our sleep habits?

Posted: 03 Feb 2017 08:26 PM PST

For example, if days lasted 48 hours on Earth instead of 24 hours, would humans have adapted to stay awake for all the daylight hours and sleep for twice as long or do humans biologically need around 8 hours of sleep to function regardless of the amount of sunlight?

submitted by /u/airsabe
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Is the Earth the only other place in the solar system (other than the Sun) where nuclear reactions have taken place (fusion *or* fission)?

Posted: 03 Feb 2017 09:48 PM PST

Effects of environmental determinism on colour perception/discrimination/terms?

Posted: 03 Feb 2017 06:38 PM PST

I know there has been a lot of research on colour term universality vs linguistic relativity, but does anybody know of much research on environmental determinism or other forms of determinism (e.g. lifestyle) on colour perception, discrimination, number of basic colour terms in language, etc.?

Berlin & Kay (1969:15-17) speculate a little about why industrialised societies seem to have more colour terms but it's all very speculative and it's not based on anything empirical. Has anybody does any research on these sorts of topics since then?

Thanks for your help!

submitted by /u/l33t_sas
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If you put an object that was perfectly red in a room with absolutely no red wavelengths, what colour would it be?

Posted: 03 Feb 2017 07:30 PM PST

Asking because I know objects are certain colours because of the light they reflect. So if there were no wavelengths of that colour to reflect, but there was still visible light to illuminate it, what would you see?

submitted by /u/RubberyBannana
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What keeps neutrons in the nucleus of an atom?

Posted: 03 Feb 2017 03:39 PM PST

They have no charge so what force keeps the neutrons in the nucleus?

submitted by /u/morseerman
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[Physics] What happens to neutrons that are ejected from nuclei through various processes (fission, knocked out by high energy photons, etc)?

Posted: 03 Feb 2017 12:41 PM PST

Do they just float around in space or do they attach themselves to existing atomic nuclei? Is there a significant amount of exclusively neutron material in our universe that simply exists unbonded to an proton? I don't think I've ever heard of neutrons existing by themselves outside of special cases like a neutron star (exclude these cases), so it made me curious.

submitted by /u/kentuckyk1d
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Stabilization of N- and C-terminus in amino acids?

Posted: 03 Feb 2017 09:15 PM PST

My professor stated that an amino acid like glutamic acid will lower the pKa of one of the COOH groups to dissociate its proton, while the other COOH group while increase its pKa to prevent dissociation (which would cause repulsion due to like charges).

I can't seem to find this anywhere in my textbook or online. Can anybody confirm if this is correct, and if so, what effects does this have on amino acids on a larger scale?

submitted by /u/blackphonecover
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Can paper products be used to sequester carbon?

Posted: 03 Feb 2017 12:39 PM PST

With concerns about CO2 emissions and talks about deforestation releasing sequestered carbon, I'm curious about factory farms and their ability to sequester carbon. Trees essentially turn air into wood, wood which is pulped up into paper, paper that is then thrown away or recycled.

I'm wondering if subsidizing paper products to increase the number of factory farms could have any signifant impact on the amount of CO2 in the atmosphere.

submitted by /u/therationalpi
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Since electron energy levels are discrete, why are absorption spectra continuous?

Posted: 03 Feb 2017 01:51 PM PST

It's pretty standard in intro-level chemistry or physics to talk about absorption/emission spectra that have discrete lines like this, where each line corresponds to an electronic transition. Pretty simple. But I've found that absorption curves (like this) come up more often, and I can't figure out how the continuous peaked curve corresponds with the quantum image.

I've been under the impression that absorption curves are also produced by electronic transitions, so I don't quite get what the difference between the two is, and under which conditions each would be produced. All I can really say is that I've done tons of spectroscopy tests that produced curves, and never whatever type of test is necessary to produce the discrete spectra.

I'm guessing it has something to do with the thermal energy of the individual atoms and molecules, which is variable in a sample and thus produces slightly different transition energies for each molecule?

I'm also pretty sure I'm conflating at least a couple concepts here.

Thanks

submitted by /u/newappeal
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Are there any animals that build upon the tools/structures/techniques they utilize from generation to generation?

Posted: 03 Feb 2017 11:31 AM PST

Similar to humans in that we learn and adapt from those who came before us. Is a beaver dam more structurally sound today than it would have been 400 years ago? Is a happy face spiderweb stronger through geometric design today than in the past? Do animals use better materials for their tools now than they did 50 generations ago?

submitted by /u/MrAloha808
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I have many questions about melanocytes; Does melanocyte distribution affect skin-tone evenness, and if so, what affects the distribution of melanocytes? Do darker-skinned people have more melanocytes, or just make more melanin? etc.

Posted: 03 Feb 2017 11:13 AM PST

What I (think that I) know:

I know that melanin is a skin pigment that determines how dark or tan a person is, and that it's production is somewhat determined by genetics combined with UV exposure. From my understanding, things like freckles, age spots, melasma, and general uneven skin tone are all caused by an uneven distribution of melanin in the skin. It is also my understanding that treatments (such as hydroquinone) aimed at improving the evenness of skin tone - or even just overall lightness - often work by targeting melanin production and somehow inhibiting or reducing the amount of melanin produced by cells, whereas other treatments (like lasers and IPL and chemical peels) destroy or break apart or burn-off the melanin. I've even heard of a drug (Melanotan) that increases melanin production to make someone more tan. And finally, I've learned that melanin is produced by certain cells called melanocytes, and that treatments aimed at changing pigmentation often are targeting the action of these cells, and that melanoma is specifically cancer of these cells.

What I don't get:

Where my understanding falters, is in why melanin is produced more in one spot of skin than another, or more in one person than another, and how that is determined by melanocytes. Do people with darker skin have more melanocytes, or just produce more melanin with the ones they have? Why would a melanocyte two inches over from another, with the same amount of UV light exposed to it, produce a big blob of melanin (an age spot or freckle) whereas the other didn't? Or is the case that the melanocytes aren't evenly distributed themselves - in which case, why does that happen? And related to that, if melanocytes aren't distributed evenly, why don't skin care treatments target the cells themselves, instead of their action? Is it possible to target and destroy melanocytes like the procedures that destroy hair follicles for permanent hair removal? Or is there a way to grow or even transplant more melanocytes where they are lacking (like how hair follicles are moved to treat male-pattern baldness)? And if melanocytes are moved with a skin graft (like in a burn patient) - do those melanocytes act the same as they always did, or do they change based on new factors (like host genes)? Would skin donated by a tan person stay tan if transplanted to a less-tan person, or would it fade over time? Even more curious to me, is what about melanoma in relation to melanin and melanocytes distribution? I've heard that people who are tan have less likelihood of getting it - but wouldn't they either have less melanocytes, or less active ones? Wouldn't they be at a lower risk of their melanocytes growing and dividing out of control, then? Or are they at greater risk for melanoma in the same way that they are at greater risk for other melanin-related pigmentation changes like age spots, and if that's the case, would it decrease someones cancer risk if they could get more melanocytes and/or produce more melanin (or more evenly)?

That's a lot of questions, I know - but I appreciate any responses!

submitted by /u/waitwuh
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If I stretch a metal bar, it becomes thinner at one point, and then suddenly it snaps. What is the molecular-level reason why it doesn't keep becoming thinner and thinner?

Posted: 03 Feb 2017 07:08 AM PST

Eg see here https://www.youtube.com/watch?v=fnkSLZKxlRk

I understand the material stretch curve and elastic-inelastic deformation, but what "changes" between the regime where the material is stretching in inelastic deformation and the regime where it just suddenly snaps?

submitted by /u/esbio
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Why do I see the dark part of a crescent moon?

Posted: 03 Feb 2017 05:37 PM PST

When it's a crescent moon I can obviously see the crescent made of the sun's light reflected off the moon. But I also can make out the dark disc of the unlit remainder of the moon. Why is that? My guess would be that the dark part is fractionally lit enough for me to differentiate it from the light reflecting off the atmosphere but I'd like to be sure.

submitted by /u/CorporalCalamity
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Friday, February 3, 2017

AskScience Panel of Scientists XVI

AskScience Panel of Scientists XVI


AskScience Panel of Scientists XVI

Posted: 02 Feb 2017 04:54 PM PST

Please read this entire post carefully and format your application appropriately.

This post is for new panelist recruitment! The previous one is here.

The panel is an informal group of redditors who are either professional scientists or those in training to become so. All panelists have at least a graduate-level familiarity within their declared field of expertise and answer questions from related areas of study. A panelist's expertise is summarized in a color-coded AskScience flair.

Membership in the panel comes with access to a panelist subreddit. It is a place for panelists to interact with each other, voice concerns to the moderators, and where the moderators make announcements to the whole panel. It's a good place to network with people who share your interests!


You are eligible to join the panel if you:

  • Are studying for at least an MSc. or equivalent degree in the sciences, AND,

  • Are able to communicate your knowledge of your field at a level accessible to various audiences.


Instructions for formatting your panelist application:

  • Choose exactly one general field from the side-bar (Physics, Engineering, Social Sciences, etc.).

  • State your specific field in one word or phrase (Neuropathology, Quantum Chemistry, etc.)

  • Succinctly describe your particular area of research in a few words (carbon nanotube dielectric properties, myelin sheath degradation in Parkinsons patients, etc.)

  • Give us a brief synopsis of your education: are you a research scientist for three decades, or a first-year Ph.D. student?

  • Provide links to comments you've made in AskScience which you feel are indicative of your scholarship. Applications will not be approved without several comments made in /r/AskScience itself.


Ideally, these comments should clearly indicate your fluency in the fundamentals of your discipline as well as your expertise. We favor comments that contain citations so we can assess its correctness without specific domain knowledge.

Here's an example application:

 Username: /u/foretopsail General field: Anthropology Specific field: Maritime Archaeology Particular areas of research include historical archaeology, archaeometry, and ship construction. Education: MA in archaeology, researcher for several years. Comments: 1, 2, 3, 4. 

Please do not give us personally identifiable information and please follow the template. We're not going to do real-life background checks - we're just asking for reddit's best behavior. However, several moderators are tasked with monitoring panelist activity, and your credentials will be checked against the academic content of your posts on a continuing basis.

You can submit your application by replying to this post.

submitted by /u/AskScienceModerator
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AskScience AMA Series: I'm Lawrence Krauss, Chair of the Board of Sponsors of the Bulletin of the Atomic Scientists, ask me anything!

Posted: 03 Feb 2017 04:00 AM PST

Lawrence Krauss, a renowned theoretical physicist, is director of the Origins Project at Arizona State University as well as the Chair of the Board of Sponsors of the Bulletin of the Atomic Scientists, who recently moved the Doomsday Clock 30 seconds closer to midnight. He is the author of more than 300 scientific publications and nine books, including the international bestsellers, A Universe from Nothing, The Physics of Star Trek, and the upcoming book The Greatest Story Ever Told--So Far. The recipient of numerous awards, Krauss is a regular columnist for newspapers and magazines, including The New Yorker, and he appears frequently on radio, television, and in feature films. Krauss lives in Portland, Oregon, and Tempe, Arizona.

Lawrence will be joining starting around 2 PM ET (19 UT).

submitted by /u/AskScienceModerator
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Do all galaxies have a very massive object at their center? If so, is it necessarily a black hole?

Posted: 03 Feb 2017 04:51 AM PST

why can't particles of zero mass be at the rest?

Posted: 02 Feb 2017 06:23 PM PST

in a book I'm reading it says the fact that a particle has zero mass means, in a way, that it cannot be at rest. why is that?

submitted by /u/throwaway_justaway
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Why is lead always the element used to protect us from radiation?

Posted: 02 Feb 2017 03:19 PM PST

To expand a bit, what properties does lead have that make it so good at protecting from radiation. How does it actually keep the radiation from touching us? What is happening at the atomic level?

submitted by /u/The_Astronautt
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Is there any evidence that pheromones play an active role for mating in humans?

Posted: 02 Feb 2017 06:15 PM PST

Do our pupils dilate when we dream about light?

Posted: 02 Feb 2017 11:56 AM PST

Last night I dreamt about being in a very dark room for a long time. Eventually I walked outside and was met by this very bright daylight. It hurt my eyes, but the pain eventually disappeared, as it would in a real life situation, because of our pupils adjusting.

I found this very fascinating, because it's probably all imaginary, but it felt so real. Do our eyes react to imaginery impulses, like in this case, (bright) light in a dream?


PS: I don't know the antonym of dilating in the context of pupils, so I stuck with it in the title.

submitted by /u/TheApeirophobe
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Is our galaxy on a stable axis?

Posted: 02 Feb 2017 10:31 AM PST

Watching this video, I started to wonder, if a rotating object in zero-G is on an unstable axis, the object will rotate on a different intermediate axis to try and correct the instability.

Does the Milky Way Galaxy also rotate like this? Does a lack of rotation suggest a stable axis?

submitted by /u/truemeliorist
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If you drill a hole in a metal plate and then freeze the plate, does the hole get smaller, bigger or stays the same?

Posted: 02 Feb 2017 08:32 AM PST

Where do the electrons go in a Neutron Star?

Posted: 02 Feb 2017 11:37 AM PST

I have been reading a little bit about neutron stars and I think they are really fascinating. However, I've never understood where the electrons go when the atoms collapse into neutrons. It was explained to me that the protons in the nucleus absorb the electrons, giving the atom a neutral charge. But, neutrons are made up of 2 down quarks and an up quark without an electron in it. So what happens to the electron?

submitted by /u/floppymcschloppy
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Why is there only positive or negative electric charges?

Posted: 02 Feb 2017 05:25 PM PST

How do we know there is no "sub-negative" or "sub-positive" charges, or even a whole different set of undiscovered charge values?

submitted by /u/ExtrahCrispy
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Why do antihistamines cause drowsiness when they cross the Blood Brain Barrier?

Posted: 02 Feb 2017 05:59 PM PST

This article explains it well,

First-generation antihistamines are highly lipophilic and therefore readily cross the blood-brain barrier, contributing to adverse central nervous system effects including sedation, drowsiness, and decreased cognitive processing

but it does not specify why first-generation antihistamines cause drowsiness when they cross the BBB. What effects do these antihistamines have on the central nervous system once it crosses the barrier?

submitted by /u/kuhataparunks
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[Mathematics] Does df/dx behave like a fraction?

Posted: 02 Feb 2017 09:58 AM PST

If df/dx=2x with f=x2, is df/2x=dx? We had this question when we were doing integration with substitution. Some said no because it's an operator not a fraction but it does in fact work if you use it for integration.

submitted by /u/Tirunculus
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[Chemistry] What is smell?

Posted: 02 Feb 2017 04:20 PM PST

I know that smell is essentially molecules attaching to smell receptors in our noses(correct me if I'm wrong). So does that mean when something smells, it's "decomposing"(the source's particles escaped?)? What causes smell to originate from the source?

submitted by /u/explo_e-the-unknown
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If two astronauts are traveling half the speed of light away from each other, and looking behind them, what would they each see?

Posted: 02 Feb 2017 07:09 AM PST

How does lasing cause transitions from the metastable state when by definition the selection rules forbid it?

Posted: 02 Feb 2017 10:32 AM PST

I have a basic question about laser physics that doesn't seem to be answered in any of the standard introductory books on my shelf.

I understand that in order to create a population inversion you need to excite transitions to a metastable state, and that the lasing occurs with stimulated emission of transitions from the metastable state. However, this seems to be a contradiction in terms, which is strangely not addressed anywhere I can find online or in my textbooks! For example, in 'Modern Physics' by Thornton & Rex, they say:

"The key is that the transition from E2 to E1 must be forbidden, for example, by a Delta l = +- 1 selection rule. Then the state with energy E2 is said to be metastable."

And then a few lines later they say that the lasing transition is the stimulated emission of exactly the previous transition they just described as "forbidden." And certainly the aforementioned selection rule would prevent the stimulated emission by a photon of spin 1 angular momentum, since the metastability is due to such a transition not being possible (for example the metastable state being in the 2s state, so the only lower state is 1s, so a transition would have Delta l = 0, which is not allowed).

What am I missing?

submitted by /u/ButWhoIsCounting
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How does corking a baseball bat cause the ball to travel further when hit?

Posted: 02 Feb 2017 09:11 AM PST

Affinity chromatography or coimmunoprecipitation: When should someone use one or the other?

Posted: 02 Feb 2017 05:41 PM PST

I feel like they're both too similar. I can't really imagine a situation best suited for one, because it feels like they essentially perform the same function.  

Take the following problem, for example:

A protein called p21 is an inhibitor of cell division in human cells. Mutations that inactivate p21 are an important cause of cancer because they cause unrestrained cell division. Imagine that you are one of the first people to study p21 and you hypothesize that it inhibits cell division by binding and inhibiting cyclin-dependent kinase (CDK), which is the kinase that initiates and controls the process of cell division. What would be the easiest way to test whether p21 binds to CDK? Briefly explain how the test would be carried out.

The answer to this question is Coimmunoprecipitation, using an antibody to precepitate p21 or cdk then using Western Blotting/mass spec.  

Why can't affinity chromatography be used in this situation instead? Does anyone know any specific examples where one would be a better choice than the other?

submitted by /u/thathomelessguy
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Before it was possible to repair an ACL with surgery, were there any treatment options for those who suffered one?

Posted: 02 Feb 2017 09:18 AM PST

Could perpetual motion be created somehow in a vaccum chamber with zero gravity?

Posted: 02 Feb 2017 06:50 AM PST

I feel like without any air resistance or gravity there would be no force to slow down the perpetual motion device. Am I correct?

submitted by /u/SwiftnovaXG
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Thursday, February 2, 2017

If an astronaut travel in a spaceship near the speed of light for one year. Because of the speed, the time inside the ship has only been one hour. How much cosmic radiation has the astronaut and the ship been bombarded? Is it one year or one hour?

If an astronaut travel in a spaceship near the speed of light for one year. Because of the speed, the time inside the ship has only been one hour. How much cosmic radiation has the astronaut and the ship been bombarded? Is it one year or one hour?


If an astronaut travel in a spaceship near the speed of light for one year. Because of the speed, the time inside the ship has only been one hour. How much cosmic radiation has the astronaut and the ship been bombarded? Is it one year or one hour?

Posted: 02 Feb 2017 02:00 AM PST

Why do humans drink water differently from other animals?

Posted: 01 Feb 2017 09:12 PM PST

Of course I do not mean when we use cups or straws. What I mean is, imagine you fill your hands with water and raise it to your mouth to drink. How do you drink the water from your hands? I imagine you use your mouth to suck up the water. However when I observe my pets (cat and dog) drinking water from their bowl, they use their tongue to lap the water into their mouths. I'm not sure how other mammals do it as I have not really paid attention. I am curious why mammals would have different ways to drink water. Do other apes drink water in the same way as humans? Is the difference due to mouth/jaw physiology?

submitted by /u/MyRandomQuestions
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Would a hydrophobic surface reduce the drag of an aerodynamic object traveling in air at all?

Posted: 01 Feb 2017 08:41 PM PST

It has been shown that a superhydrophobic surface can significantly reduce the drag on an object submersed in water (not really experimentally shown on a large scale due to issues with surfactants I think). See this reference for instance:

Extraordinary drag-reducing effect of a superhydrophobic coating on a macroscopic model ship at high speed. By Hongyu Dong

I wanted to know if a drag reduction effect can still hold if we made two changes. i) the object was moved to air rather than water and ii) the surface was made to be hydrophobic rather than superhydrophobic.

My thinking is that if the object is traveling in air, there will still be a thin film of air pinned to the object, right? And this thin film will then help keep the surrounding flow laminar, or at least more laminar than without the hydrophobic coating. Of course, the drag might not see a significant reduction but I just want to know if it works at all.

submitted by /u/synergistali
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Why "1 + 1 = 2" ?

Posted: 31 Jan 2017 10:55 PM PST

I'm a high school teacher, I have bright and curious 15-16 years old students. One of them asked me why "1+1=2". I was thinking avout showing the whole class a proof using peano's axioms. Anyone has a better/easier way to prove this to 15-16 years old students?

Edit: Wow, thanks everyone for the great answers. I'll read them all when I come home later tonight.

submitted by /u/ehh_screw_it
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*Where* is the "hologram?"

Posted: 02 Feb 2017 06:58 AM PST

Having seen several recent news articles suggesting the first evidence seen regarding the universe as a hologram, along with older information on the theory (a lot from Susskind) I find myself still unclear on the location of information in a holographic universe.

Are they positing that it is all on an event horizon of the entire universe and completely non-local, or is it local, but all on a 2D surface at Planck scales?

submitted by /u/Hailbacchus
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How are intermontane basins formed?

Posted: 01 Feb 2017 08:24 PM PST

I understand that they are located within and in-between mountain ranges, and I've read online that the basins are often formed as a result of grabens. However, I can't figure out how the extensional forces required for graben formation could appear in such a region.

submitted by /u/geonerdSO
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Why is it that the medial branches of the dorsal rami innervate the cutaneous tissue of the upper back, but the lateral branches of the dorsal rami innervate the cutaneous tissue of the lower back?

Posted: 01 Feb 2017 08:25 PM PST

When will Alaska touch Russia, and what will happen geologically?

Posted: 01 Feb 2017 08:21 PM PST

Hello r/askscience, This is my first time asking any questions here, but I was wondering about something that Google searches failed me on, when will Alaska touch Russia. I know that it is approximately 55 miles between the tip of Alaska and Russia, but it brings up the question when will the land mass make contact? Furthermore, what will geologically happen. These areas have been separated from what I have heard since prehistoric times, so will we massive extinction of certain species since animals haven't adapted to Russian wildlife?

submitted by /u/evievi002
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How do we calculate million/billion plus half lives of elements?

Posted: 01 Feb 2017 03:37 PM PST

Why does the iron filings and bar magnets experiment result in the iron filings arranging themselves in neat lines when the magnetic field should be continuously distributed around the magnet?

Posted: 01 Feb 2017 11:53 PM PST

How does drinking water clear the bad stuff out of our bodies?

Posted: 01 Feb 2017 08:37 PM PST

Does distilled VS stilled water make a difference? How does it help our skin? Just curious how it actually works inside of our bodies. Always heard that drinking water can flush all the bad stuff out. Esp after a greasy, fat meal.

submitted by /u/Hf4444
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What happens with fat and muscle tissue when there is no food consumption?

Posted: 01 Feb 2017 07:38 PM PST

Why is it said that muscle tissue is broke down when you don't eat? Isn't the whole purpose if storing fat to use it when energy is needed?

submitted by /u/FiggerNugget
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What does the solubility of a chemical in powder form (Allopurinol) mean when I want to make solution?

Posted: 02 Feb 2017 03:04 AM PST

I am looking selleckchem.com at a powder reagent of Allopurinol. I am planning to use it for an experiment. However, the site also shows the solubility in vitro with water at 4 mg/mL (29.38 mM). If I want to make a working concentration of 10 uM (10 umol/L) in a 2 mL aliquot, how do I factor in the solubility of this reagent in water? I apologize in advance, this is all information I should probably understand. This is the link if you want to see what I mean.

http://www.selleckchem.com/products/Allopurinol(Zyloprim).html

submitted by /u/Opirr
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Does non-photonic energy count towards the total mass-energy of a system?

Posted: 01 Feb 2017 04:58 PM PST

If I have a massive system that is just on the edge of collapsing into a black hole and I add mass, it collapses. If I shoot it with a laser, it collapses, because the photons put it over the edge as their gravitation adds to the system.

But what if I kick it and start it rotating? Does that rotational energy add to the system's mass-energy and put it over the edge? What if I linearly accelerate it? Or if I reshape it so that it is two shells, and then apply a voltage between the shells, adding energy due to capacitance? If I cooled it down, would I be taking it further from collapsing (assuming no density changes)?

If I started to create a cavity at the center of it by pushing outward, thereby increasing the gravitational potential energy of the system (and assuming no change in outer radius), would it collapse?

submitted by /u/justpassingthroo30
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Why are all ferroelectric materials also piezoelectric?

Posted: 01 Feb 2017 09:04 PM PST

I've been reading up on the piezoelectric effect which brought me to the ferroelectric effect and it said that all ferroelectric materials are also piezoelectric but I can't seem to find an explanation for why that is?

submitted by /u/usthrowaawaayy
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I just heard that it would take 4 light-years of lead to stop a neutron. This seems like it leaves out how fast the neutron is moving. How fast or why not?

Posted: 01 Feb 2017 02:58 PM PST

Were nuclear weapons a straightforward result of nuclear theory? Or was it more complicated than that?

Posted: 01 Feb 2017 01:07 PM PST

Once scientists understood how nuclear reactions occurred, were nuclear weapons an obvious/straightforward application of nuclear theory?

(Clearly there are serious practical problems in designing and testing a working mechanism, refining the material, etc, but I'm mostly asking about the initial realization of "hey, I wonder if we could make a really big bomb using this!")

Sure, anyone could plug numbers into e=mc2, but that doesn't necessarily imply you could actually use it for something.

Or to approach the same question in another way: were nuclear weapons developed independently by multiple countries, after the US demonstrated their potential? Or did they all rely on a common body of work?

submitted by /u/MegaTrain
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What is the line below the nose but above the mouth on mammals called, and what is it for?

Posted: 01 Feb 2017 01:07 PM PST

For clarification purposes: http://imgur.com/MuJfwj2

I've been googling around trying to find out what that is caled. It's seen on many mammals and seems to be a defining feature, enough so where the emoticon :3 is identified as a cat. However, unsurprisingly, looking up "what is the line below nose and above mouth called" or any permutation that makes sense yields no relevant results.

submitted by /u/Mister4Eyes
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Why can't we control our heart beat, what physically stops us from controlling those types of muscles?

Posted: 01 Feb 2017 04:41 PM PST

Why does the integral of 1/x result in a logarithm? Also, why does logarithm have base e?

Posted: 01 Feb 2017 09:52 AM PST

I think it seems too beautiful and amazing that this is just a coincidence that the integral of 1/x results in a logarithm (much less for that logarithm to have a base of one of the most useful numbers in mathematics, e) for it to just be coincidence. Can someone come up with a proof, or at least a logical argument, for why this is the case?

submitted by /u/ThePurplePancake4
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Does the intermediate axis theorem have any recapitulation in the switching of the magnetic poles of the Earth?

Posted: 01 Feb 2017 03:14 PM PST

Can a child end up with more than 50% of their genes from the father?

Posted: 01 Feb 2017 08:02 PM PST

So I got into this discussion with my SO after watching Game of Thrones

Let's say we have a husband (call him dad) and he has a child with his wife. The child (lets call him child #1 and make her a female) would have 50% of each parents genes. Now if the husband (dad) has sex with child #1 and has child #2, then child #2 would have 50% of the dad's gene and 50% of child #1 genes. But child #1 has already 50% of the dad's gene, would child #2 have 75% of the dads gene? What if this process continues many more times? Would the last child have more of the dads gene then just a half?

submitted by /u/Tunafish7428
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Does an empty refrigerator use less energy than a full refrigerator?

Posted: 01 Feb 2017 04:02 PM PST

After the contents of the full fridge have cooled, which one is more efficient to keep cool?

submitted by /u/ThreeFistsCompromise
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