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Thursday, January 14, 2021

Do animals that sleep in multiple short "naps" (such as cats) require REM sleep the way humans do?

Do animals that sleep in multiple short "naps" (such as cats) require REM sleep the way humans do?

Do animals that sleep in multiple short "naps" (such as cats) require REM sleep the way humans do?

Posted: 13 Jan 2021 10:26 PM PST

Is sound, bound by gravity? Is screaming upwards any different than sceaming downwards, speed or volume-wise?

Posted: 13 Jan 2021 02:15 PM PST

Are more contagious viruses less fatal/dangerous? If so, why?

Posted: 14 Jan 2021 06:18 AM PST

When pain tolerance is plotted on a graph what type of growth pattern does it tend to follow?

Posted: 13 Jan 2021 08:11 PM PST

Have there been any studies where painful stimuli is increased and the people tested update their perceived level of pain? I'm familiar with the experiment where people put their hand in cold water and the duration they can withstand is timed, but that experiment doesn't increase the intensity of the stimulus because the water temperature stays constant or slightly warms over time.

Have there been any experiments where an electrical current is applied, people report how much pain they feel, then a stronger electrical current is applied and the new level of subjective pain is reported? If so, what does the graph of electrical current to reported pain look like? Does this vary among different population groups?

I'm especially curious about the growth of the graph (i.e. linear, exponential, logarithmic). I'm also curious if there are people with low pain thresholds who also have high pain tolerance. For example, they might have a graph like y = 0.1x while someone with high pain threshold but low pain tolerance might have a graph like y = -5 + 3x.

Also, do different sources of pain change reported experience of pain? For example, do some people have a higher resistance to heat induced pain than electrical induced pain? Are there any patterns among which types of groups are most resistant to which types of pains? I've read that runners tend to have higher pain tolerance, but I'm wondering if this has been analysed by source of pain. For example, maybe people from cold climates have a higher tolerance to cold stimuli? Or people from areas with many mosquitoes have a higher tolerance to mosquito bites? If so, when a person from a cold climate moves to a hot climate does their tolerance to cold stimuli change?

submitted by /u/sooneday
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What makes a voice unique?

Posted: 13 Jan 2021 03:49 PM PST

Pitch is just the vibration of vocal chords at a certain speed to generate a certain wavelength right? So why do two people singing at the same pitch sound different?

P.S. not sure if I used the right flair because I'm not sure what impacts it, sorry 😅

submitted by /u/Pause_Remarkable
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What are the raw materials for mRNA vaccines and where do they come from?

Posted: 13 Jan 2021 12:25 PM PST

I have some understanding of how the COVID-19 vaccine was designed and works thanks to this article. It talks about using a DNA printer to create the molecule. Further research told me that bulk manufacturing uses "bioreactors".

But what are the actual raw materials and where are they obtained from? I got some vague answers of "enzymes" and "polymerases" from a lot of searching. What are the actual raw materials and where are they obtained from?

I am looking for answers on the lines of -> it uses "x" which is obtained by refining soy protein, "y" which is obtained from fractional distillation of crude oil, and "z" by fermenting cat pee etc. Where do the chemicals used in the bioreactor/DNA printer come from?

submitted by /u/dranzerfu
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Is there any issue with having a variety of Covid-19 vaccines out there?

Posted: 13 Jan 2021 05:10 PM PST

It just seems that most developed country have three vaccines approved for usage now, and likely at least one more will be approved shortly.

Is there any issue rolling out a bunch of difference vaccines to combat one virus?

submitted by /u/falsekoala
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Is the universe flat or 3D? Basically, as the universe is expanding, is it going in all directions or just in one plane?

Posted: 13 Jan 2021 08:47 PM PST

What makes the new Coronavirus-mutation from UK and South-Africa more contagious?

Posted: 13 Jan 2021 11:54 AM PST

Do other mammals have an umbilical cord, and if so, how is it cut?

Posted: 13 Jan 2021 08:29 AM PST

How would a meteorologist calculate or estimate the TOTAL amount of precipitation that falls in an area/state/country?

Posted: 13 Jan 2021 05:18 PM PST

If you look up the rainiest states in the U.S. for instance it goes by average precipitation. It says 22 inches of precipitation fell in California, which is obviously some kind of average. What's the TOTAL amount of rain/snow that fell in California? Surely it would be much more than a smaller state like Hawaii, which is listed as the rainiest place in the U.S..

submitted by /u/THCarlisle
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How do then figure out that more then one doses of a vaccine will make a person immune when testing a vaccine?

Posted: 13 Jan 2021 01:05 PM PST

I mean if the first doses doesn't work what makes them believe more doses will?

submitted by /u/kingofstars1
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Why does the lack of smell impairs the sense of taste?

Posted: 13 Jan 2021 03:26 AM PST

why do vaccines need to be put in a vial?

Posted: 13 Jan 2021 10:34 AM PST

can they not just deliver it in big jugs with self adhessive cap where syringe needles can be inserted to extract some. that way you need less resources to make the vials and can deliver larger quantities

submitted by /u/shoaibnasiri
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How does the new covid mRNA vaccines avoid destruction by siRNA or microRNA?

Posted: 13 Jan 2021 04:28 AM PST

Hey everyone, I am a medical student and recently we learned about siRNA and microRNA and how they silence mRNA transcription and helps degrade them. So i was wondering how the new covid_19 mRNA vaccines are able to bypass this system. And whether or not this can be a form of resistance to the new vaccines?

submitted by /u/Drpaper123
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Why does hot asphalt look reflective at low angles?

Posted: 12 Jan 2021 09:56 PM PST
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Wednesday, January 13, 2021

Is it possible to have steam hot enough to start a fire?

Is it possible to have steam hot enough to start a fire?

Is it possible to have steam hot enough to start a fire?

Posted: 13 Jan 2021 05:48 AM PST

As in igniting f.ex. paper.

submitted by /u/Majestic-Throat-2249
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AskScience AMA Series: We're a team of scientists and communicators sharing the best of what we know about overcoming COVID-19 vaccine hesitancy - Ask us anything!

Posted: 13 Jan 2021 04:00 AM PST

Soon, the COVID-19 vaccine will be available to everyone. Public health professionals are asking how to build confidence and trust in the vaccine. We're here to answer some of those questions. We're not biomedical scientists, but our team of experts in psychology, behavioral science, public health, and communications can give you a look behind the scenes of building vaccine confidence, vaccine hesitancy and the communications work that goes into addressing it. Our answers today are informed by a guide we built on COVID-19 vaccine communications on behalf of Purpose and the United Nations Verified initiative, as well as years of experience in our fields.

Joining today are Ann Searight Christiano, Director of the University of Florida Center for Public Interest Communications; Jack Barry, Postdoctoral Fellow at the University of Florida Center for Public Interest Communications; Lisa Fazio, Assistant Professor of Psychology at Vanderbilt University; Neil Lewis, Jr., a behavioral, intervention, and meta-scientist, as well as Assistant Professor in the Department of Communication at Cornell University and the Division of General Internal Medicine at Weill Cornell Medicine; Kurt Gray, Associate Professor in Psychology and Neuroscience at the University of North Carolina at Chapel Hill; and Jonathan Kennedy, Senior Lecturer in Global Public Health at Barts and the London School of Medicine and Dentistry, Queen Mary University of London. - Ask us anything.

Our guests will join at 1 PM ET (18 UT), username: /u/VaccineCommsResearch

submitted by /u/AskScienceModerator
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Why is argon used in dark matter detection experiments?

Posted: 12 Jan 2021 03:56 PM PST

In XENON experiments, why is argon specifically used rather than any other element?

submitted by /u/Direct-Ad8432
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How bright would a single light have to be to be visible from the moon?

Posted: 13 Jan 2021 07:17 AM PST

Specifically lights that shine in a cone such that they could be pointed at the moon and be visible from anywhere facing the earth, as opposed to lasers which would only be visible from a small area Also assuming the area the light is shone from is in night and free from external light pollution

submitted by /u/ibrokemypie
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Ask Anything Wednesday - Engineering, Mathematics, Computer Science

Posted: 13 Jan 2021 07:00 AM PST

Welcome to our weekly feature, Ask Anything Wednesday - this week we are focusing on Engineering, Mathematics, Computer Science

Do you have a question within these topics you weren't sure was worth submitting? Is something a bit too speculative for a typical /r/AskScience post? No question is too big or small for AAW. In this thread you can ask any science-related question! Things like: "What would happen if...", "How will the future...", "If all the rules for 'X' were different...", "Why does my...".

Asking Questions:

Please post your question as a top-level response to this, and our team of panellists will be here to answer and discuss your questions. The other topic areas will appear in future Ask Anything Wednesdays, so if you have other questions not covered by this weeks theme please either hold on to it until those topics come around, or go and post over in our sister subreddit /r/AskScienceDiscussion , where every day is Ask Anything Wednesday! Off-theme questions in this post will be removed to try and keep the thread a manageable size for both our readers and panellists.

Answering Questions:

Please only answer a posted question if you are an expert in the field. The full guidelines for posting responses in AskScience can be found here. In short, this is a moderated subreddit, and responses which do not meet our quality guidelines will be removed. Remember, peer reviewed sources are always appreciated, and anecdotes are absolutely not appropriate. In general if your answer begins with 'I think', or 'I've heard', then it's not suitable for /r/AskScience.

If you would like to become a member of the AskScience panel, please refer to the information provided here.

Past AskAnythingWednesday posts can be found here. Ask away!

submitted by /u/AutoModerator
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How did they discover the new variants of COVID-19?

Posted: 12 Jan 2021 01:13 PM PST

So obviously the Covid-19 PCR test is being used quite a lot today but how was the new variant discovered. Did the test start giving false negatives more frequently or is the virus constantly being monitored?

If the virus is constantly being studied I have some follow up questions

Where do the samples come from? Would they need the consent of the patient who has given the sample to study it? Is the only reason they're screening the virus to detect variants?

submitted by /u/Low_Celery_5978
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How does scientist determine if the measured vaccine efficacy is statistically significant?

Posted: 13 Jan 2021 12:42 AM PST

I read an article that said Pfizer deduced its covid vaccine efficacy to be 95% because of the 170 participant involved the clinical trial who got sick, only 5% of them were in the vaccine group (the rest is in placebo group), the difference is statistically significant enough to conclude the drug works.

I want to ask how do scientist determine whether the vaccine is statistically significant or not?

submitted by /u/lifesaboxofchoco
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What causes abrubt drops in the ISS altitude?

Posted: 12 Jan 2021 11:28 AM PST

This Link shows a plot of the ISS vss time on the heavens above website. As indicated by the caption, occassional boosts are used to raise the orbit which decays over time. There are however multiples where there are abrupt drops in the ISS altitude, some of them greater in magnitude and just as fast as the boost phase raises. What causes these? This does not seem to be consistent with the cited "solar activity".

submitted by /u/shiningPate
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What is the difference, in terms of the electrons motion, between the valence band and the conduction band?

Posted: 12 Jan 2021 01:39 PM PST

Could somebody clarify this? It's to my understanding that electrons in the valence band are bound to the atom they are paired with, while the electrons in the conduction band aren't associated with any given atom, and are free to roam. Is this true?

submitted by /u/magginator8
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Would the protonation of an alcohol be exothermic or endothermic?

Posted: 11 Jan 2021 06:15 PM PST

I'll be basing this off the equilibrium R-OH + H+ <==> R-OH2+ :)

From what I understand, bond making processes are exothermic because energy is released when bonds are formed, and an additional O-H bond is formed in the equilibrium here, thereby making it exothermic. Since -OH alone is a poor leaving group and protonating it makes it a better leaving group therefore making it more reactive, wouldn't that then put R-OH2+ at a higher energy level than R-OH? (If we were drawing an energy diagram)

But if the more reactive R-OH2+ is at a higher energy level then that means it must be endothermic on that diagram?

I'm really confused, hopefully someone can clarify this for me :)

submitted by /u/Zealousideal_Low1200
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vào lúc No comments:

Tuesday, January 12, 2021

If the near centre of a record rotates in 1 second (1cm/second) what would happen if the record was 1000's of metres wide?

If the near centre of a record rotates in 1 second (1cm/second) what would happen if the record was 1000's of metres wide?

If the near centre of a record rotates in 1 second (1cm/second) what would happen if the record was 1000's of metres wide?

Posted: 12 Jan 2021 12:09 AM PST

If the record had a big enough diameter, and it was possible to actually turn it, why wouldn't it be going faster than light?

submitted by /u/tinox2
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Will you still feel hungry when nutrients are artificially sent through your bloodstream?

Posted: 11 Jan 2021 04:19 PM PST

How is hunger replenished? Does the lack of nutrients of your cells send signals to the brain to tell that your hungry or does it have to do with the stomach, etc.?

submitted by /u/ThrowAway1200221
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How does any photon reach exactly the energy needed to excite a particular atom?

Posted: 11 Jan 2021 08:45 AM PST

I know that quantum mechanics states that some things, like bumping an electron to a higher energy level, requires something like a photon to have juuuuust the right energy for the electron to 'accept' that photon and then rise to the higher energy level.

But it is always explained that it has to be exact. Like, EXACT exact. It must be, let's say, 10,854.7952 electron volts, which corresponds to a frequency of 12.795832 GHz (ignore the actual values, I just pulled some numbers out of my head). It is always explained that if it were even slightly higher or lower than that amount of energy, the electron wouldn't be excited by it.

Well, what are the odds that a photon with that very very VERY exact energy level would come passing by in any reasonable amount of time? I know photons are a tiny amount of energy and there are a huge number of them all the time, but still, it seems like such a precise requirement would be very restrictive, and would result in almost no interactions between particles and the EM force.

It seems like all my assumptions can't be right here. What am I missing?

submitted by /u/tazz2500
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Why do flames flicker at a relatively consistent rate?

Posted: 12 Jan 2021 04:39 AM PST

In the following paper, one can see that different flames flicker at 10-12Hz. However, I cannot understand the paper itself. Could anyone simplify why it's the case that seemingly unrelated types of flames flicker at a really specific frequency?

Chen, T., Guo, X., Jia, J. et al. Frequency and Phase Characteristics of Candle Flame Oscillation. Sci Rep 9, 342 (2019). https://doi.org/10.1038/s41598-018-36754-w

submitted by /u/jul3q
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Are the two doses of COVID vaccine exactly the same?

Posted: 11 Jan 2021 02:40 PM PST

Two gorillas were just diagnosed with Covid in CA. What does Covid look like in animals and can a disease, like covid, pose a significant risk to a specieces if there is rapid transmission?

Posted: 11 Jan 2021 02:03 PM PST

Is there a scientific/mathematical name for the gradient at which a substance such as sand will begin to fall down if collected into a pile?

Posted: 12 Jan 2021 06:34 AM PST

Would an astronaut in a spaceship in geostationary orbit, feel their own weight and be able to stand on the "floor" of the spaceship?

Posted: 11 Jan 2021 05:14 PM PST

Follow my line of thought here, and let me know where my understanding breaks down please. As I understand it, astronauts feel weightless in orbit because they are in a free-fall around the Earth, not because there is no gravity. Earth's gravity is still acting upon the astronaut, but to a lesser degree than if the astronaut was on the ground. If someone built a tower from the ground to, say, where the ISS orbits, wouldn't someone be able to stand on the tower and feel their weight because they are not in a free-fall? Less weight than they would feel on the ground, but some weight. If that is true, let's say someone built a tower up to where geostationary orbit is. Someone should still be able to stand on the tower and feel some weight, right? From that observers perspective, being in a spaceship in geostationary orbit and on a tower at the same height should feel the same correct? Neither are moving with respect to the ground, and they are the same distance from Earth so the effect of gravity is the same.

submitted by /u/VVolfLikeMe
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What's the role of washing soda in making of glass?

Posted: 12 Jan 2021 04:14 AM PST

What makes a pathogen highly infectious?

Posted: 11 Jan 2021 04:25 PM PST

Does the pathogen replicate like crazy basically oozing out of the body? Is it from the symptoms they cause that they take advantage of? Is it from the amount of viruses or bacteria it takes to infect you?

submitted by /u/817mkd
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What happened to caterpillar's DNA after it methamorposes into butterfly?

Posted: 11 Jan 2021 11:34 PM PST

Is it still the same or is it changed/rearranged?

submitted by /u/IEatYourRamen
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Why do rockets and other space probes spin/roll?

Posted: 11 Jan 2021 07:30 PM PST

Like for example take the Perseverance rover. In the animation that NASA uses, it shows the entry capsule to be spinning through space, and once they hit the Martian atmosphere, reverse thrusters stabilize it. Is spinning your way through space somehow important or beneficial?

​

PS. First time posting anything on Reddit, please forgive and tell me if I did something wrong XD

submitted by /u/another-moron
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Where do we get stomach flu viruses from?

Posted: 11 Jan 2021 01:12 PM PST

We've been in this pandemic for quite some time now. Me and my family have been very precautious by respecting all the measures that were suggested to avoid catching the virus. However, a couple of months ago I caught a bad stomach flu. I had a fever (38.5/39 °C at its peak) and a very violent diarrhea. I got tested for covid through swab test since my doctor said that those can be symptoms for that, but results came back as negative. Also other members of my family got tested a couple of weeks after as a precaution and those also came back as negative. I didn't have any other symptoms other than those and feeling very weak because of all the fluids I lost and poor sleep. My doctor said that it must've been a stomach flu, like I've caught in the past occasionally. A couple of weeks ago the same exact thing happens to my sister's boyfriend. Again, his test's negative, same symptoms, no contact in recent times with other people, everyone else tests negative for covid, etc. Possibly another stomach flu case.

That got me thinking: with no contact outside of my few household members (and they're doing the same, being very careful) and everyone in my neighborhood (thankfully!) wearing masks while buying grocheries, social distancing, washing hands carefully, etc. where the heck do we get viruses from? Specifically, stomach flus in this case?

submitted by /u/-NotFBI
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How are the Black Sea and Caspian Sea not considered lakes in this day and age?

Posted: 11 Jan 2021 08:31 AM PST

I'm not sure if this belongs here or not, but this has just been bugging the crap out of me for awhile now. To my knowledge any inland body of water that is not directly connected to an ocean is considered a lake, yet the Black Sea and Caspian Sea are still called seas even though they are completely surrounded by land. Is there a logical explanation to explain this or is it literally as simple as a "can't be bothered" thing to do?

submitted by /u/MrCriminalScum
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Theoretically, is it possible for an mNRA vaccine to contain more than one genetic code?

Posted: 11 Jan 2021 03:27 PM PST

Has there been an increase in heart attacks and strokes this year due to COVID?

Posted: 11 Jan 2021 06:39 PM PST

I've seen multiple studies that point to strokes and heart attacks maybe about a month later after a person being diagnosed with COVID. Is this something that has been common with COVID, and has there been a spike in heart attacks and strokes due to COVID?

submitted by /u/bhood1992
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What is the equation for elastic potential energy of a rubber ball?

Posted: 11 Jan 2021 06:11 PM PST

In physics class, they always talk about the elastic potential energy objects that stretch in one dimension, like springs. In those cases, the elastic potential energy is given by

E = 1/2 k x2

And then the force is the derivative

F = - k x

But if you compress a ball (like if you hold a ball on its sides and push the bottom on the floor), not all parts of the ball are displaced the same amount from their starting point. So is x is that case the greatest displacement? The average displacement? The average displacement weighted by displacement squared? Something else?

submitted by /u/JokdnKjol
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when could a teen get a covid-19 vaccine?

Posted: 11 Jan 2021 05:21 PM PST

I've heard from many people that teens will not be able to get a covid-19 vaccine even after it is available to the public. I've heard the vaccines like moderna and Pfizer are only available for use for 18 and up, But I've also heard Johnson & Johnson are studying it? I would be very upset if I'm not able to get it because I wont feel safe going to school

submitted by /u/fvdly_tyler
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where are the stars in the constellation of aries?

Posted: 11 Jan 2021 02:50 PM PST

so for a project of mine i was curious: where exactly are the stars in aries if you where to look topdown on our galaxy? would they be towards the rim or the center? im kinda banking on the rim here for my idea to work.

submitted by /u/KRANOT
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vào lúc No comments:

Monday, January 11, 2021

When we use tools like uranium dating and carbon dating to identify the ages of objects, how are we sure of the starting concentration of those materials such that we can date the objects by measuring the concentration of those materials remaining in the objects?

When we use tools like uranium dating and carbon dating to identify the ages of objects, how are we sure of the starting concentration of those materials such that we can date the objects by measuring the concentration of those materials remaining in the objects?

When we use tools like uranium dating and carbon dating to identify the ages of objects, how are we sure of the starting concentration of those materials such that we can date the objects by measuring the concentration of those materials remaining in the objects?

Posted: 10 Jan 2021 10:57 AM PST

Would donating plasma post vaccination help someone as much as donating post infection? I recently received my second jab, and would like to donate whole blood or plasma after a couple of weeks. Do you think that my blood or plasma could be used to treat a patient with severe covid?

Posted: 10 Jan 2021 01:06 PM PST

Does a Molten Salt Nuclear Reactor require a heat sink such as a large body of water like a river or lake? If a Molten Salt Type does require water as a heat sink, does it use more or less water than other types of fission reactors?

Posted: 10 Jan 2021 09:15 PM PST

Are you allowed to have sex after getting a Covid Vaccine?

Posted: 10 Jan 2021 08:55 PM PST

My boss mentioned that he isn't getting the vaccine because of XYZ. One thing he mentioned, which stuck out to me, was that you aren't allowed to have sex for 29 days. I tried asking him why but wasn't able to give an answer. I googled it for a while and didn't find anything. Is there any truth to this?

submitted by /u/Kwkyo
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What would happen if a positron encountered a negative muon?

Posted: 10 Jan 2021 07:01 PM PST

As is common knowledge among the physics community when positrons encounter electrons they mutually annihilate each other into two high-energy gamma rays. Though what would happen if a positron encountered a negatively charged muon? Seeing as though they have opposite charges you would expect the same result. However, what would be leftover looking at how the muon is 207 times more massive than an electron? Would the new particle only be 206 times "heavier" than an electron? Would it now have a neutral charge? Would the particle still be short-lived and unstable like ordinary muons? If yes, what particle would it decay into? Why?

submitted by /u/Dumbustafa1
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Would it be possible or practical to simulate potential mutations in SARS-CoV-2 in order to discover and anticipate new variants?

Posted: 10 Jan 2021 02:38 PM PST

I've heard of projects simulating protein folding from DNA, and I understand some of a virus' abilities come from the proteins encoded in its RNA. Are we able to compute virus properties and activity from arbitrary RNA?

submitted by /u/anonymous_coward
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Do new viruses ever spread across the world without people noticing?

Posted: 10 Jan 2021 12:56 PM PST

COVID-19 is deadly. But what if it weren't? What if there were a similarly infectious condition that didn't cause serious health effects? How would we even notice it? I read the book Germs years ago and was surprised at how long it took to identify outbreaks of serious disease. So is it possible that there are less deadly novel viruses that spread around the world and aren't noticed?

submitted by /u/TrueBirch
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Is it possible to transfer a vaccine through bodily fluid?

Posted: 10 Jan 2021 09:23 PM PST

I just had a thought. Vaccines are dampened or harmless versions of viruses right? So could those be transmitted through bodily fluids, sexually, sharing needles etc? not saying I'm going to do it, I'm just curious.

submitted by /u/gogetmymoneyclip
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Any evidence on the safety of COVID long-haulers receiving the vaccine?

Posted: 10 Jan 2021 09:13 AM PST

I was wondering if anyone with knowledge of the Pfizer/Moderna vaccine had thoughts on if people who have already had COVID and have long-term symptoms would be safe getting the vaccine? Or if there are any potential downsides? Is it worth taking the chance?

submitted by /u/thewrongrecroom
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Are there corresponding HSV/RGB values to natural pigments? (Carotenoids, chlorophylls)

Posted: 10 Jan 2021 12:30 PM PST

Are there corresponding HSV/RGB values to natural pigments? (Carotenoids, chlorophylls).

submitted by /u/nojobnoproblem
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I’ve always seen these fun videos on YouTube about interesting science experiments and I’ve come across one that shows people making near-unbreakable glass “teardrops,” called, Prince Rupert’s Drops. Why do these drops take so much pressure to break?

Posted: 09 Jan 2021 07:58 PM PST

Is there any reliable information as how effective the Chinese Coronavirus Vaccine is?

Posted: 10 Jan 2021 01:57 AM PST
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