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Wednesday, February 26, 2020

Are Tardigrades susceptible to viral and/or bacterial infection? Can they get ‘sick’?

Are Tardigrades susceptible to viral and/or bacterial infection? Can they get ‘sick’?

Are Tardigrades susceptible to viral and/or bacterial infection? Can they get ‘sick’?

Posted: 25 Feb 2020 06:45 PM PST

AskScience AMA Series: We are Christiana Figueres and Tom Rivett-Carnac, Executive Secretary of the United Nations Framework Convention on Climate Change 2010-2016 and a senior member of the UN team that created the Paris Agreement on Climate Change, our new book The Future We Choose is out! AUA!

Posted: 26 Feb 2020 04:00 AM PST

We were two of the lead negotiators of the Paris Climate Agreement, and continue to dedicate our careers and lives to stopping the climate crisis -- Christiana was Executive Secretary of the United Nations Framework Convention on Climate Change (UNFCCC) 2010-2016 and Tom was a senior member of the UN team that created the Paris Agreement on Climate Change, signed by 195 countries in 2015. AUA!

** We are at a critical decision making moment that will determine the entire future of humanity.** This year and the next ten are going to have more of an impact on the future of the Earth than any other decade in history. We are facing either a world of breakdown and conflict, of floods and disasters that will be close to home more quickly than we could have imagined, where hope has slipped away - OR - a world that is renewed, where forests have regrown and cities are remade, where your children are not afraid to have children of their own. That reality is overwhelming for most of us because we don't know what to do about it.

While we do not deny that daunting challenges are ahead, we do not agree with the idea that we are somehow already doomed to a devastating future or that humanity is somehow flawed and incapable of responding to big problems; we are fully convinced that we can avert the worst of the climate crisis through a change of mindset and the ten actions outlined in our book.

We are really excited to be here today to answer all of your questions around climate change and creating together the world that we all hope to see -- and live in! We will be here at 4:30pm ET today, so ask us anything and let's talk about how to wade through all of the existing news and information about climate issues, and really distill it all down so we can each create our own action plans to collectively survive the climate crisis.

You can see more on our book at https://globaloptimism.com and also connect with us further on Twitter at @cfigueres and @tomcarnac. We also host a podcast called Outrage & Optimism where we interview journalists and global leaders on how to drive social and environmental change.

Again, our guests will be here at 4:30pm ET (21:30 UT).

submitted by /u/AskScienceModerator
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How far would we have to move Earth’s orbit to return global temperatures to pre-industrial levels?

Posted: 25 Feb 2020 11:55 AM PST

What makes some kinds of leafy greens edible, and others not?

Posted: 25 Feb 2020 11:53 AM PST

Ask Anything Wednesday - Economics, Political Science, Linguistics, Anthropology

Posted: 26 Feb 2020 07:09 AM PST

Welcome to our weekly feature, Ask Anything Wednesday - this week we are focusing on Economics, Political Science, Linguistics, Anthropology

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!

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What is happening when the blood 'drains from your face'? And where is it going?

Posted: 25 Feb 2020 04:01 PM PST

Just finished the Chernobyl series on HBO. Could someone explain what positive and negative void coefficients are and why they exist? And what about a reactor design can make such a dramatic difference?

Posted: 25 Feb 2020 09:05 PM PST

if you can see the sun and the moon at the same time, what happens on the other side of the world?

Posted: 25 Feb 2020 04:52 PM PST

Why are black holes often displayed with acreation disk which is red to orange on the outer rim and yellow to white on the inner ring?

Posted: 25 Feb 2020 03:22 PM PST

Im in process of painting Binary black holes and Im using some images as reference. I was wanderimg why are black holes often displayed with acreation disk which has darker colors (orange to almost red) on the outer rim and lighter colors(yellow to almost white) on the inner ring, closer to core (or horizon). Is there science behind this "popular" picture of black holes?

And any science or knowledge behind "Binary black holes" you could share?

Thank you for any answer.

submitted by /u/Zourtyx
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Why are most of the oldest living people in the world female?

Posted: 25 Feb 2020 04:24 PM PST

According to this list most of the oldest living people in the world are female. Why is that the case?

submitted by /u/seriousnotshirley
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Why do cell membranes not aggregate?

Posted: 25 Feb 2020 09:20 AM PST

I was wondering why cell membranes don't tend to aggregate together? Lipids in suspension tend to aggregate over time, especially when they're kept at higher temperatures (like physiological temperature), so why is it that this doesn't occur with cells?

Thanks!

submitted by /u/fappyboyjohnson
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Which forces make atomic lattice so strong?

Posted: 25 Feb 2020 09:32 AM PST

atomic lattice materials are more durable than others (diamond for example)

Why? There is low electronegativity that would keep the atoms together. Is there any other forces bonding it together and making material so durable rather than electromagnetism?

Atomic lattice has covalent bonds, which are weaker than ionic ones, because of electronegativity. But it still have the most durable items.

Please correct me. I am newbie in chemistry, but i am curious about it and i want to know.

submitted by /u/blaurisb
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How does carbon dating actually work? Do they just see how much carbon has decomposed? If so, how can they tell how much was originally there?

Posted: 25 Feb 2020 08:07 AM PST

Why do cells gain water in a hypotonic solution if substances move from areas of higher concentration to lower concentration?

Posted: 25 Feb 2020 09:24 AM PST

If a cell is surrounded by a solution that contains a lower concentration of water, why does the water move into the cell? Wouldn't the water from inside the cell move to the outside into the surrounding solution, since there is a lower concentration of water outside?

submitted by /u/MikestheDyke
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How does nuclear fusion in the Sun produce the sunlight we see on Earrh?

Posted: 24 Feb 2020 10:13 PM PST

What happens to an insect’s body when you spray it with insecticide?

Posted: 24 Feb 2020 09:58 PM PST

Obviously, it dies, but what happens internally? Whenever I spray roaches point-blank, they scurry rapidly but when you bop them, they flip over and their legs flail wildly in the air until they start twitching in their death throes.

Do they get paralyzed? Are their nerves on fire? Is it the equivalent of napalm on humans?

submitted by /u/narookoo
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Are all organisms on earth from the same event, or did life occur several times and evolved into different paths?

Posted: 24 Feb 2020 11:43 PM PST

Back in school, we had this linear timeline on how amoebas evolved into more advanced lifeforms over time.

Mushrooms, plants, bacteria, fish, mammals, reptiles and birds etc. Do we all share the same origin ?

submitted by /u/faced88
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Can someone please explain how Cliffs are formed?

Posted: 24 Feb 2020 07:49 PM PST

I saw the cliffs in Moher, Ireland in a picture and I can't understand how they were formed.

I looked it up, and I understand that an ancient river deposited layers of sedimentary rock, and then the ocean ate away at the bottom of the rocks. This created notches and then the rock on top of the notches crumbled into the sea leaving a vertical cliff.

What I don't get is (1) how this plateau ended up so much higher than sea level before this process begun and (2) how that process would form cliffs, if there weren't already cliffs. As in, why would the ancient river's delta end up as cliffs instead of a beach?

Every cliff formation video I find seems to start with the land already higher much higher than sea level, but it's not mountains in Moher, the land is flat.

I'm thinking of the Mississippi River delta, I can't imagine enough sediment getting deposited to create a plateau that size and height above sea level. How would the river keep depositing sediment when the plateau becomes higher than sea level?

Help pls. Lol

submitted by /u/Cappy11496
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Can static electricity be generated in space/orbit?

Posted: 24 Feb 2020 06:42 PM PST
vào lúc No comments:

Tuesday, February 25, 2020

AskScience AMA Series: I'm Giulio Guzzinati and I use transmission electron microscopes to look at the nanoworld and play around with the wave functions of electrons.

AskScience AMA Series: I'm Giulio Guzzinati and I use transmission electron microscopes to look at the nanoworld and play around with the wave functions of electrons.

AskScience AMA Series: I'm Giulio Guzzinati and I use transmission electron microscopes to look at the nanoworld and play around with the wave functions of electrons.

Posted: 25 Feb 2020 04:00 AM PST

Hi Reddit!

I'm a physicists who works with with electron microscopes, particularly transmission electron microscopes (or TEMs), to look at the nanoworld and/or play around with the wave functions of electrons.

I'm originally from Italy and I work in EMAT, an electron microscopy laboratory in Antwerp, Belgium. Here ~70 researchers can use 6 TEMs study a wide variety of materials science topics, from the cathodes of Li ion batteries to the mechanics of shape memory alloys, from magnetic ceramic oxides to nanoparticle catalysts.

Why do we need electrons to image the nanoscale? The resolution of conventional optical microscopes is limited by the wavelength of the light used (0.4 µm for blue light). Electrons however are also waves, and fast electrons (i.e. accelerated with a tension above, say, 30000 Volts) have an extremely short wavelength, of only a few picometers. Using electromagnetic fields we can steer and focus these electrons beams just like we do on light by using glass lenses. We get resolutions all the way down to 0.05 nm, that is a twentieth of a millionth of a millimeter (or 2 billionths of an inch in freedom units). This is such a good resolution, that it allows us to even look at the atoms that make up solid materials! (No, seriously, how cool is that??) We use these capabilities to study the link between the microscopic structure and shape of materials and their macroscopic properties.

My personal focus is on the development of methodologies, that is I try to find ways to use or misuse electron microscopes to measure the proporties of the samples with better precision, clarity or even study things that we couldn't before. For instance, I recently demonstrated a new method to measure deformations (strain) in materials with nanometer resolution with a precision of up to 1 part in 5000, which is very important when prototyping or producing semiconductor devices. A more exotic interest of mine is that of wave function manipulation. Since the state and properties of the electrons are defined by their wavefunction, we can give them new and interesting properties intentionally changing the wavefunction. It's a bit like having a quantum sandbox. I did plenty of research on electron vortex beams, a weird type of beam rotating around its own axis which therefore possesses it's own magnetic moment, and interacts with mangnetic fields in a peculiar way, but also others such as the Airy waves, which possess freakish properties such as accelerating in absence of external forces.

If you want to know more about my research, here is my Google Scholar profile, all of my articles on the arXiv.

I will be here between 12:00 EST (17:00 UTC, 18:00 CET) and 16:00 EST (21:00 UTC, 22:00 CET) to answer your questions.

Giulio

submitted by /u/AskScienceModerator
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Is there any dry land on Earth composed of oceanic crust?

Posted: 24 Feb 2020 10:04 AM PST

Any region, no matter how small. I was looking at a map of plate boundaries and it seems that all oceanic crust is below sea level; but I was wondering if there were any exceptions.

submitted by /u/hdk759
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Do coal plants give off radiation?

Posted: 24 Feb 2020 05:44 PM PST

Is there an instance in which land is subducted under land instead of converging?

Posted: 24 Feb 2020 10:22 PM PST

What exactly is “Muscle Memory”?

Posted: 24 Feb 2020 07:19 AM PST

How does practicing a skill, let's say tennis, one day; effect your future performance in days/months time. Is it mainly the strengthening of neural pathways that relates to muscle behaviour, or is it more complex?

submitted by /u/bash_mead
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If I placed a sufficiently large block of lead, or other dense, massive object, next to one of the arms of the LIGO detector, would its gravitational influence be detectable by LIGO?

Posted: 24 Feb 2020 09:40 PM PST

How much bacteria is actually killed in a Microwave or Oven?

Posted: 24 Feb 2020 01:16 PM PST

Weve all reheated food in an oven or microwave and accidentally left it in there longer than intended. Sometimes overnight, sometimes just for an hour.

I know heat generally kills germs, being a main point of cooking in the first place, as well as radiation kills everything living.

That being said, lets say I had some food microwaved for a full minute, and just leave it in there for a week. Would there be mold in it now? Or is everything so dead, that life cannot exist.

Same thing for something being in an oven, except lets say the food was there for an hour or 2 at 400 degrees(F).

submitted by /u/DarkLordKindle
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How does the Pilot wave theory explaine the collapse of the interference pattern upon placing a detector at one of the slits in the double slit experiment?

Posted: 24 Feb 2020 12:52 PM PST

I get the collapse of the wavefunction in the Copenhagen interpretation, does the same happen to the wavefunction in pilot wave theory? If so why, and also when does it happen, immediately when the detector is placed even before the particle is close to the slit?

submitted by /u/fruitydude
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How were the photographs of Betelgeuse taken?

Posted: 24 Feb 2020 04:38 AM PST

In astronomy 101 I learned that stars are point sources of light. Even the most powerful optical telescope cannot resolve a star into a disk. If this is still true, how were the recent photographs of Betelgeuse taken? Are these photographs at all or are they digital representations of spectrographic data? (with apologies to the moderators for second pass at this)

submitted by /u/Banister_Fletcher
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How are fast neutrons and thermal (slow) neutrons created in a fission reaction?

Posted: 24 Feb 2020 09:44 AM PST

I'm studying nuclear reactions and I came across the notion of fast neutrons and thermal neutrons and I can't quite wrap my head around it..

Aren't all neutrons resulting from a nuclear fission roughly the same speed? What I mean by this is, the instant the nucleus undergoes fission, aren't the neutrons ejected at roughly the same speed?

If so, are thermal neutrons slow only because they bounced around a lot and thus got slowed down by molecules? And fast neutrons are just "lucky" ones?

Thanks in advance

submitted by /u/snigzou
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Why induction pans must be ferromagnetic?

Posted: 24 Feb 2020 11:14 AM PST

From my understanding, in order to generate heat in an induction cooktop, you need Foucault currents inside the material. This generates the electric energy that will be dissipated as heat by the pan acting as a resistor.

The thing is, to generate those currents the only requisite is that there is a variable magnetic field acting on a conductor, so there's no ferromagnetism acting there.

My only guesses are that either those currents are amplified by the magnetic field created by the ferromagnetic material or that the resistance of the material is somehow dependant on the magnetic response of the material. (Or I'm completely wrong in the physics behind it)

Thanks in advance

submitted by /u/DenyGrante
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Why is nomex (meta-aramid fiber) heat resistant?

Posted: 24 Feb 2020 06:13 AM PST

Nomex shows excellent heat resistance. At molecular level, what makes it heat resistant? For example, kevlar has high tensile strength due to H-bonding. Similarly what makes nomex heat resistant.

submitted by /u/fecklessTurd
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What physically happens when you adapt to colder regions?

Posted: 24 Feb 2020 09:18 AM PST

I recently moved to Buffalo, NY from Southern California and it got me curious as to how the body adapts to cold.

submitted by /u/dashingalpaca
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Does the brain control anything that isn't a muscle?

Posted: 23 Feb 2020 09:55 PM PST

I was thinking about the signals that go into and out of the brain. There's plenty of variety of what goes in: sight, sound, balance, taste, temperature, pain... the list is nearly endless. But when it comes to output, I couldn't think of anything that wasn't a muscle. The heart's a muscle. Vocal cords are a muscle. Eye movement is controlled by muscles. Does the brain control anything that's not a muscle?

submitted by /u/Code__Cube
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Why don't mangroves grow in temperate climates?

Posted: 24 Feb 2020 07:03 AM PST

Somebody asked this question in a thread about DnD, and it made me really curious. Mangroves grow almost exclusively in the tropics. Swamps grow in the South, but never the more temperate zones. Is there any particular reason that how wet or dry a forest is seems to be correlated with latitude?

submitted by /u/Dorocche
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How do cells use energy from ATP for movement?

Posted: 24 Feb 2020 05:53 AM PST

How does the energy from chemical bonds power biomechanical processes?

submitted by /u/SirDanilus
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Question about severe dehydration?

Posted: 24 Feb 2020 09:29 AM PST

Remember at the end of WWII when the Jews were liberated from the concentration camps and the allies gave them food and because they had been starved for so long, eating a bunch of food actually killed some of the survivors? My question is can the same thing happen with dehydration: can you be so severely dehydrated that drinking a shitload of water will kill you or is it totally fine to drink like crazy. Thanks!

submitted by /u/NoOneForACause
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Monday, February 24, 2020

How do we know the magnitude of TREE(3)?

How do we know the magnitude of TREE(3)?

How do we know the magnitude of TREE(3)?

Posted: 23 Feb 2020 11:54 AM PST

I've gotten on a big number kick lately and TREE(3) confuses me. With Graham's Number, I can (sort of) understand how massive it is because you can walk someone through tetration, pentation, etc and show that you use these iterations to get to an unimaginably massive number, and there's a semblance of calculation involved so I can see how to arrive at it. But with everything I've seen on TREE(3) it seems like mathematicians basically just say "it's stupid big" and that's that. How do we know it's this gargantuan value that (evidently) makes Graham's Number seem tiny by comparison?

submitted by /u/GoalieSwag
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What makes a sugar be a sugar? And what makes it taste sweet?

Posted: 23 Feb 2020 07:14 PM PST

If fusion power was as widespread as fission today, what would the worst case "meltdown" scenario be and how bad would it be compared to fission meltdowns?

Posted: 23 Feb 2020 04:50 PM PST

If fusion power was as widespread as fission today, what would the worst case "meltdown" scenario be and how bad would it be compared to fission meltdowns? Why?

submitted by /u/V0yagerXyX
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What causes glass to be transparent? If atoms are mostly empty space, then why can't photons pass through that space and make every substance transparent?

Posted: 23 Feb 2020 03:10 PM PST

Were Velociraptors as dangerous/deadly as Jurassic Park depicts them to be?

Posted: 23 Feb 2020 09:03 PM PST

Why are some creeks particularly sandy?

Posted: 23 Feb 2020 07:17 PM PST

I live in the Appalachian piedmont, and the creek nearest me is the sandiest creek that I have ever seen in this area. It's typically clay here (metro Atlanta), and I have been wondering why this one's so different.

submitted by /u/delladoug
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How does mixing work? Why can't we unmix stuff?

Posted: 24 Feb 2020 12:54 AM PST

Why is it that after we mix two groups of things eg. 100 red marbles and 100 blue marbles, the marbles more or less look homogenized and we can never get two separate groups of red and blue again? Is there some sort of permutation probability effect in play here?

submitted by /u/kaddymate
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Is the shallow increase in water depth on Florida's West coast and the sharp increase in water depth on Florida's East coast a function of meteorology (e.g. prevailing winds, hurricanes, etc) or some other forces?

Posted: 23 Feb 2020 04:16 PM PST

As seen in this map, the depth of the water off the West coast of Florida gradually increases in depth whereas the depth of the water off the East coast rapidly increases: https://i.imgur.com/t943C74.jpg

submitted by /u/iiwfi
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If we find oil on another planet how many theories will it change/confirm?

Posted: 23 Feb 2020 07:17 PM PST

Why are female cheetahs solitary?

Posted: 23 Feb 2020 03:09 PM PST

Apparently female cheetahs are always solitary if they don't have cups, while male cheetahs form groups and hunt together. So I'm wondering: What causes female cheetahs to be solitary? When it comes to cats, lions and such, it's usually males who are territorial, while females are less territorial if at all I believe. What makes cheetahs the opposite in this aspect?

submitted by /u/Pharmafairy
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Do we know what birds communicate about?

Posted: 23 Feb 2020 03:40 AM PST

Does anyone study bird communication? Can we translate what birds talk about?

submitted by /u/LaVerdadEsQue
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Why do chicken egg yolks have so much cholesterol?

Posted: 22 Feb 2020 09:24 PM PST

Google says chicken egg yolks have approximately 180 mg of cholesterol per 17 g of yolk. This number seems shockingly high. What does a developing chick do with all that cholesterol? I thought cholesterol was an energetic dead end so only steroids and hormones make sense to me. Pork sausage on the other hand is about 54 mg per 76 g, around an order of magnitude lower per gram.

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Why are so many medicines incompatible with alcohol?

Posted: 22 Feb 2020 05:36 PM PST

Does supermassive black hole size correlate with the size of the galaxy or are they unrelated?

Posted: 22 Feb 2020 08:37 PM PST
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