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Thursday, July 9, 2020

AskScience AMA Series: Are there really aliens out there? I am Seth Shostak, senior astronomer and Institute Fellow at the SETI Institute, and I am looking. AMA!

AskScience AMA Series: Are there really aliens out there? I am Seth Shostak, senior astronomer and Institute Fellow at the SETI Institute, and I am looking. AMA!


AskScience AMA Series: Are there really aliens out there? I am Seth Shostak, senior astronomer and Institute Fellow at the SETI Institute, and I am looking. AMA!

Posted: 09 Jul 2020 04:00 AM PDT

I frequently run afoul of others who believe that visitors from deep space are buzzing the countryside and occasionally hauling innocent burghers out of their bedrooms for unapproved experiments. I doubt this is happening.

I have written 600 popular articles on astronomy, film, technology and other enervating topics. I have also assaulted the public with three, inoffensive trade books on the efforts by scientists to prove that we're not alone in the universe. With a Boulder-based co-author, I have written a textbook that I claim, with little evidence, has had a modestly positive effect on college students. I also host a weekly, one-hour radio show entitled Big Picture Science.

My background encompasses such diverse activities as film making, railroading and computer animation. A frequent lecturer and sound bite pundit on television and radio, I can occasionally be heard lamenting the fact that, according to my own estimate, I was born two generations too early to benefit from the cure for death. I am the inventor of the electric banana, which I think has a peel but has had little positive effect on my lifestyle -- or that of others.

Links:

I'll see you all at 10am PT (1 PM ET, 17 UT), AMA!

Username: setiinstitute

submitted by /u/AskScienceModerator
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Why is the Chernobyl New Safe Confinement dome only good for 100 years?

Posted: 08 Jul 2020 03:29 PM PDT

Is it only needed for 100 years, or will something occur to it to make it inoperable? And what is it actually made out of?

submitted by /u/ThatBlueSkittle
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Why can I smell a smoker from 30-60ft away but coronavirus social distancing is set at 6ft?

Posted: 09 Jul 2020 07:46 AM PDT

The real question is why does smoke linger in the air at such great distances but supposedly corona virus does not. What is the difference?

submitted by /u/awardsforthee
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While faster, 5 GHz Wi-Fi signals do not penetrate walls as effectively as 2.4 GHz signals. What is the actual physical explanation for this?

Posted: 08 Jul 2020 06:02 PM PDT

What is it about the higher frequency of the EM-wave that makes it worse at penetrating walls?

Or is it more like a small "reverse-window" of a frequency range that is at that point worse at penetrating walls and gets better again at some point (an even higher frequency)? And if so, why would it be like this?

Because I can't imagine this trend to continue forever, otherwise we wouldn't need lead to block ionizing radiation which obviously has an even higher frequency than 5 GHz?

submitted by /u/Lego_ergo_sum
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Is there a website or study/modeling where it predicts future climate/weather patterns for specific areas of the U.S.?

Posted: 09 Jul 2020 03:57 AM PDT

I'm planning on moving from Florida in a few years and the lion's share of my reasoning is this State's climate future. Looking at certain areas with an enlightened prospectus regarding where this area is heading climate wise would be very helpful.

Possibly regarding Michigan's upper peninsula (Marquette) and I'm thinking the weather will become just more extreme at both ends (harsher/colder winters, hotter summers) but would be nice to have an expert's opinion.

submitted by /u/Al_Kydah
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What was the most powerful volcano ever known to mankind?

Posted: 08 Jul 2020 09:45 PM PDT

What was the most powerful volcano ever known to mankind and how does it compare to the Hiroshima bombing?

submitted by /u/Uncle_Iroh2
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How come current reverse transcriptase inhibitors don't work against SARS-CoV-2?

Posted: 08 Jul 2020 05:07 PM PDT

Since inhibitors for the reverse transcriptase enzyme exist and are used in the treatment of AIDS patients, I wondered why they don't work for SARS-CoV-2. Aren't enzymes like those conservated so they can't be that different? Or don't we have an inhibitor for the catalytic center and other surfaces of the protein mutate to not be targetable?

submitted by /u/Maultaschtyrann
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If a drug made an AIDS patient immune to HIV, would they recover?

Posted: 08 Jul 2020 11:52 AM PDT

I was just wondering this and, for once, the internet didn't answer my question. I don't do biology, but I understand the HIV virus kills T-cells and how that causes AIDS.

Assuming a hypothetical treatment that rendered one immune to HIV through any mechanism whatsoever, such that the virus could not exist in their body, does the immune system recover? Do T-cells regenerate or does the virus somehow alter the way in which the body produces them?

Assuming one does recover, does that mean current treatments that reduce an AIDS patient's viral load to undetectable levels cure AIDS (assuming permanent treatment)?

submitted by /u/CromulentInPDX
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Does laminar flow hold on a small - (microscopic, atomic), level?

Posted: 08 Jul 2020 02:08 PM PDT

I know that laminar flow is much less common than turbulent flow, but when you get down to a small cross-section of laminar flow, is it all laminar down to the atomic scale? Or, is it that laminar flow is composed of small turbulent flows on a small scale that average to a laminar state of the system? Thanks!

submitted by /u/holdensintheguglag
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How many of the Milky Way's stars have been well characterized?

Posted: 08 Jul 2020 06:43 PM PDT

How many of the 100 billion or so stars in our galaxy do we know anything about?

For instance, say "well characterized" means we know the stars' position in the sky well enough to point a telescope at it, we know its distance from us and relative velocity to within a factor of 2, and we know its stellar classification. Are most of the stars in our galaxy this well characterized? The half on our side of the centre? Just a small fraction? I hope at least all the naked eye visible stars are.

Thanks

submitted by /u/suoirucimalsi
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How exactly does the strong force work?

Posted: 08 Jul 2020 09:09 AM PDT

I recently learned that the strong force binds protons together in the nucleus of an atom, but what exactly is the strong force? Does it only work for protons or does it occur when any two charges are close enough?

submitted by /u/Mono-light
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How important is it for children to see faces for their social development and language skills?

Posted: 08 Jul 2020 02:52 PM PDT

Why is the surface of the moon dusty and not solid rock from when it cooled?

Posted: 08 Jul 2020 10:26 PM PDT

For this last flu season: "Hospitalization rates in children 0-4 years old and adults 18-49 years old are the highest on record according to the CDC, surpassing the rate reported during the 2009 H1N1 pandemic." How is this possible with a quarantine during part of this last season?

Posted: 08 Jul 2020 07:39 AM PDT

Do non-Western scientists use Linnaean binomial nomenclature?

Posted: 08 Jul 2020 09:44 AM PDT

When I was in China years ago, I brought up Homo sapiens to a Chinese colleague, and she wasn't familiar with the term.

Linnaean names are Latin- and Greek-based, and I know that English is the lingua franca in the scientific community.

  • So do non-Western, non-Roman alphabet using scientists learn English and Latin/Greek to practice biology?

  • Do they have different names/systems for their own cultures?

  • And to what extent are these scientific names taught to laypeople?

submitted by /u/yo_soy_soja
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Long-Term Immunity and the Difference Between Antibodies And “Memory Cells”?

Posted: 08 Jul 2020 02:38 PM PDT

I've seen a lot of articles quoting various public agencies around the world about COVID-19 and whether or not humans develop lifetime immunity.

The general theme goes "Humans lose their antibodies within X months - and Y weeks if they were asymptomatic. As such, we may not get lifetime immunity."

Ignoring for the moment that it uses couched language of "may / may not" (and that there's no definitive proof at the moment one way or another), how is can we be inclined to think there's no immunity because antibodies fade?

Or to break the question down into more scientific components:

  • What do the presence of antibodies during a given period of time tell us about immunity generally?

  • Do antibodies stay in the body forever if we're immune to something or do they fade away and get replenished when need be by memory cells?

Thanks!

submitted by /u/Notsureifsirius
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Why will the James Webb Space Telescope put so far out in Space?

Posted: 08 Jul 2020 12:19 PM PDT

i read that the JWST will be put near the Lagrange point L2, that is a position where the gravitational forces of both Earth and Sun keeps the Telescope at the same distance to both Earth and Sun throughout the year.

what's the benefit of this? spitzer and hubble took nice photos too, and were located much much closer to earth. more like in vicinity of the iss

wiki also says, that the James Webb Space Telescope needs nevertheless a propulsion system, because adjustments are required despite being located near that "special" spot.

submitted by /u/snoo75536
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To what extent does your presupposition of a food's taste affect the actual taste once you eat it?

Posted: 08 Jul 2020 10:07 AM PDT

If you've never eaten spinach, for instance, and you are convinced that it will be the worst thing you've ever eaten, will it actually be the worst thing you've ever eaten? how much (if at all) does your perception of a potentially bad taste reflect in your actual sense of taste?

submitted by /u/nonanec9h20
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How likely is it that a person who has recovered from COVID-19 will lose their smell and taste sense forever?

Posted: 08 Jul 2020 05:36 PM PDT

If you develop antibodies for a virus only a few days after infection, why is it that an antibody test cannot detect an active infection?

Posted: 08 Jul 2020 09:37 AM PDT

Assuming that any infection (specifically viral) will remain active for at least some time after you have started to develop antibodies, wouldn't a positive antibody test and ongoing symptoms be enough to determine you have an active infection? I have seen many posts regarding the difference between COVID infection and antibody tests but nothing that explaining why an antibody test cant also detect an infection. Isn't this how testing for HIV and other viruses is conducted?

submitted by /u/1knarf1
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What is the best Calculation for how much energy is released from Volcanic Eruptions?

Posted: 08 Jul 2020 06:39 AM PDT

I have been wondering for a very long time, about how people managed to get the energy released by Volcanoes.

such as the Krakatoa Volcanic Eruption in 1883 which was around 200 megatons of TNT.

If someone could provide the answer to a valid formula that would get that amount of energy that would be great.

submitted by /u/ABCmanson
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How do bones of aquatic vertebrates like fish, whales & waterbirds compare?

Posted: 08 Jul 2020 10:20 AM PDT

Are the bones (and/or other tissues) of aquatic vertebrates similar (convergent evolution) based on the needs of dwelling in water? In what ways are the bones similar/dissimilar? [There is a theory that humans have air-filled sinuses to make our bones less dense as an adaptation to water, for example]

submitted by /u/bu11fr0g
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Wednesday, July 8, 2020

With the US now withdrawn from the WHO, how badly will that affect the seasonal flu vaccine development?

With the US now withdrawn from the WHO, how badly will that affect the seasonal flu vaccine development?


With the US now withdrawn from the WHO, how badly will that affect the seasonal flu vaccine development?

Posted: 08 Jul 2020 03:59 AM PDT

Can blood transfusions grant someone immunity to a virus that they previously had no exposure to?

Posted: 08 Jul 2020 06:21 AM PDT

If the donor already has antibodies to deal with a certain virus and the recipient didn't already have those antibodies developed, would the transfusion give the recipient the ability to make their own antibodies without exposure to the virus?

submitted by /u/BaCawBitch
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How does the immune system already have the DNA to make antibodies for new viruses?

Posted: 08 Jul 2020 02:36 AM PDT

So I get exposed to a newly evolved virus, and my body will eventually "learn" to make a protein to combat it. How? Does that genetic code already exist in my DNA and my body is just turning it on or do my cells edit DNA to make a specially designed antibody?

If it's the former, what happens if a virus evolves that doesn't match any DNA code I have for antibodies? Or is that not going to happen because they are using antigens that have to match my cell's proteins?

If it's the latter, doesn't that go against the "central dogma" of DNA that info only flows in one direction? (DNA --> Protein)

submitted by /u/Pandonia42
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Other than price and jurisdictional legal requirements, what is the actual difference between one and three year rabies vaccines for my pets?

Posted: 07 Jul 2020 11:57 PM PDT

The speed of light changes depending on the medium it is going through, does the speed of causality/information also change in different mediums?

Posted: 08 Jul 2020 12:56 AM PDT

I have seen and read that the speed of light isn't really so much the speed of light, it is the speed of any massless particle as well as the maximum speed that information and causality can travel, the maximum speed that a phenomenon can reach and affect another point in space.

Light however has different speeds when going through different mediums. Does that mean that the speed of causality also changes in different mediums or is the speed of causality the same in the vacuum as well as through glass for example?

submitted by /u/Athanatos154
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On average, how many types of antibodies for different pathogens does our body contain?

Posted: 07 Jul 2020 10:42 PM PDT

Ask Anything Wednesday - Biology, Chemistry, Neuroscience, Medicine, Psychology

Posted: 08 Jul 2020 08:08 AM PDT

Welcome to our weekly feature, Ask Anything Wednesday - this week we are focusing on Biology, Chemistry, Neuroscience, Medicine, Psychology

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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Why do neutrinos pass through objects but light can't?

Posted: 08 Jul 2020 07:23 AM PDT

I watched a video that mentioned how neutrinos from a supernova explosion reached earth before the star even exploded. And they mentioned that neutrinos way close to nothing 1,000,000 times lighter than electrons even. Does that have anything to do with the fact that neutrinos hardly interact with matter? If so, shouldn't light also not interact with objects since it is massless?

submitted by /u/ProcPhD
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Some primitive Australian and African tribes use a binary system to count. How does that work?

Posted: 08 Jul 2020 03:29 AM PDT

I was reading "understanding media" by Marshall McLuhan the other day and he mentions the following in his book:

"The most primitive tribes of Australia and Africa, like the Eskimos today, have not yet reached finger-counting, nor do they have numbers in series. Instead they have a binary system of independent numbers for *one* and *two*, with composite numbers up to *six*. After *six*, they perceive only "heap"."

How does a system like this work when you need basic numbers in pretty much every aspect of life?

submitted by /u/zeeow
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What does it really mean when they say that COVID-19 is "airborne"? How is it any different from other viral infections like the flu?

Posted: 07 Jul 2020 12:10 PM PDT

Recently, I've seen a few posts and articles pop up saying that the virus is airborne and that it lingers for a while. But isn't it known that in droplet infections, the minute droplets linger around for a bit before settling down? Haven't we already been treating it as such?

submitted by /u/the447thmilkman
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How did multicellular life appear?

Posted: 07 Jul 2020 06:23 PM PDT

Are bats recovering from White Nose Syndrome?

Posted: 07 Jul 2020 06:10 PM PDT

I live in Pennsylvania where WNS decimated the bat population. Lately I have been seeing more bats around and I am wondering if a recovery is taking place. I have not heard about the disease in a few years and have seen no new information about the topic.

submitted by /u/jbot14
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Would it be possible for a telescope to take HD photographing of Betelgeuse? If so, what would it take?

Posted: 07 Jul 2020 07:19 PM PDT

Asking because I was kind of thinking about it and how it would be impractical to send a probe given it would take at least like 1500 years to receive data

submitted by /u/Bolymoth
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How are some drugs capable of entering the blood stream through the mouth?

Posted: 07 Jul 2020 03:29 PM PDT

Drugs like immodium have variations that allow them to enter the blood stream through the mouth, and therefore faster.

Why do some drugs, like painkillers, not have this?

submitted by /u/maverickf11
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Could a combination of two or more Covid-19 vaccines boost efficacy? We could end up having with multiple safe, tested, and manufactured vaccines.

Posted: 07 Jul 2020 04:08 PM PDT

WRT possible safety, one precedent is that many older people have received two different Shingles vaccines (the newer vaccine is said to be more effective).

With Operation Warp Speed, multiple vaccines are planned to go into production before testing is completed.

submitted by /u/vtjohnhurt
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Are we able to identify different types of self-antigens?

Posted: 07 Jul 2020 07:39 PM PDT

For example, in type 1 diabetes (autoimmune disease) the CD4 and CD8 T cells identify the beta islet cells as foreign but not any of the other islet cells. Does the beta islet cell have a specific self-antigen than other islet cells?

submitted by /u/Zefyyre
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When a disease is eradicated does the pathogen get wiped off the earth?

Posted: 07 Jul 2020 11:03 AM PDT

I have a few questions about disease eradication and what it actually means --

  1. What constitutes eradication of a disease? Is there some criteria that needs to be met? Or is the pathogen completely wiped off the earth?

  2. Smallpox, for example, is eradicated. Does it mean no one can ever get it?

  3. If there is a slight chance of people getting it in the future, will we have medicines and vaccines readily available for that case? I ask because I see the cure/vaccine actually needs the pathogen or a derivative of it.

submitted by /u/yalogin
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If we cannot improve our immune systems, are the genetically predetermined?

Posted: 07 Jul 2020 02:42 PM PDT

After seeing lots of articles about foods to eat to boost immune system, I read one article that said you actually can't do anything. Does that mean our own immunity is similar to other aspects about ourselves we can't change, and why is there so much information out there that suggests we can change it by what we eat?

submitted by /u/geog15
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Can mold grow in vinegar?

Posted: 07 Jul 2020 09:05 AM PDT

Can vinegar get moldy over time? i.e. If I opened a bottle of commercial distilled vinegar and left it out unrefrigerated at what point would mold accumulate, if ever?

submitted by /u/AmericanDeise
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Tuesday, July 7, 2020

Why is a swab required to be inserted deep into your nasal cavity to determine a positive or negative covid case, yet it can be spread merely by speaking too close to somebody?

Why is a swab required to be inserted deep into your nasal cavity to determine a positive or negative covid case, yet it can be spread merely by speaking too close to somebody?


Why is a swab required to be inserted deep into your nasal cavity to determine a positive or negative covid case, yet it can be spread merely by speaking too close to somebody?

Posted: 06 Jul 2020 08:43 AM PDT

If very small transistors, like those in modern processors, were used as analog devices, would they have limited number of discrete steps based on the number of atoms in the gate?

Posted: 07 Jul 2020 05:25 AM PDT

I read that a 14nm transistor is only 67 atoms across, would that limit the resolution?

submitted by /u/DeFex
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How does blackbody radiation work?

Posted: 07 Jul 2020 05:46 AM PDT

I'm clearly stuck with some misconceptions about how blackbody radiation works, but am having trouble figuring out where my thinking is wrong. (This is not a question about uv catastrophe.) I'll try to trace my line of thinking below and would appreciate anybody pointing out my misunderstandings.

  1. When a blackbody absorbs electromagnetic radiation how that energy gets absorbed depends entirely on the radiation's frequency. Some frequencies cause molecular vibrations, rotations, bending...other specific frequencies cause election excitation.

  2. When the object reaches thermal equilibrium (determined by the absorption of frequencies causing various vibrations), it begins to emit energy to maintain an equilibrium. It emits energy both through heat and light. The light is due to only the relaxation of elections to lower energy states. This means the emitted light is only "returning" the radiation in various frequencies that went into electron excitation - not the radiation that caused vibrations.

  3. If (and that's a big if) the above is an appropriate way of describing it, it seems as though backbodies should not emit continuous spectra, but line spectra instead. I want to justify this by saying there are so many interactions in a solid that weird stuff happens with the orbitals and energy levels so there's nearly an infinite number of possible states for excited electrons. This would imply zooming enough, the continuous spectrum would actually look like a line spectrum (I know, blackbodies are an idealized situation anyway).

  4. An overarching concept: Is ALL light attributed the excitation/relaxation of electrons?

Hopefully that articulated something about what I'm trying to understand...

Thanks y'all.

submitted by /u/AsaKlubs
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If 4 out of the 7 known coronavirus types cause the common cold, then is it likely that when those 4 types first infected humans, they caused pandemics similar to COVID-19 before becoming less lethal over time?

Posted: 06 Jul 2020 10:02 PM PDT

Interested in finding out whether we know where those older common cold coronavirus types came from, and whether they could reveal how COVID-19 will end up as the SARS-CoV-2 virus continues to mutate in the future.

submitted by /u/TCTriangle
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What would happen to forests if there were no wildfires?

Posted: 07 Jul 2020 03:48 AM PDT

Does the sample size of different test groups in an experiment have an impact on the outcome of the experiment, in a medical trial?

Posted: 06 Jul 2020 11:04 PM PDT

I was reading through a journal that was testing the efficacy of hydroxychloroquine and azithromycin for treating Covid-19, and noticed that the control group (neither hydroxychloroquine or azithromycin) consisted of 409 subjects. In contrast to this, the hydroxychloroquine group had 1202 subjects.

Is there any concern for the fact that the hydroxy group is ~3 times larger than the control group? How does this effect a medical study, if at all?

The journal: https://www.ijidonline.com/article/S1201-9712(20)30534-8/fulltext

submitted by /u/Surpex
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Is abundance of near planet surface metals abundant or rare in the universe?

Posted: 06 Jul 2020 09:29 PM PDT

If the theory is true about the moon being created by a collision between Earth and a Mars-sized planet, could this also have stirred up metals to the surface of Earth? Making them available for technological advances?

If so, this could also be part of The Great Filter. Or is lava convection always going to bring up metals to the surface in Earth-like planets?

submitted by /u/nuke-from-orbit
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Do aquatic mammals drink water while swimming?

Posted: 07 Jul 2020 01:36 AM PDT

Why do bug bites itch?

Posted: 07 Jul 2020 06:36 AM PDT

How does PCR, a process used to amplify DNA, test for COVID-19?

Posted: 07 Jul 2020 02:28 AM PDT

How many electrons are used in graphene sigma bonds?

Posted: 07 Jul 2020 05:40 AM PDT

Three sp2 electrons per atom are used in sigma bonding, but each atom has 2 single and 1 double bond requiring four electrons.

Where does the extra electron come from?

submitted by /u/pag32
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Is there an equivalent to rust for plastic?

Posted: 06 Jul 2020 05:56 PM PDT

Is there any risk of covid reinfection causing cytokine storms, thus killing people?

Posted: 06 Jul 2020 02:44 PM PDT

Early on in China there were numerous examples of people walking or working, dropping dead on the spot. It was believed that maybe an immune response caused a cytokine storm due to SARS antibodies.

What happened to this theory?

Is there risk that corona could do this?

submitted by /u/GodOfTheThunder
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Are the common cold viruses really that mild or did we just never really bothered studying/tracking them?

Posted: 06 Jul 2020 05:53 PM PDT

Are the common cold viruses really that mild or did we just never really bothered studying/tracking them?

There are a few viruses causing the cold each year, some have the potential to cause more severe illness. However, there are no death rates, nothing much really mentioned about each,

submitted by /u/nilaul
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When x-rays are attenuated, what does that actually mean?

Posted: 06 Jul 2020 08:20 PM PDT

I googled that it means REDUCED IN ENERGY. But, this didn't help me much. I know bone attenuates more than air, but does this mean that the x-rays are ABSORBED by the bone more than they are by air? My textbook says that certain areas on a film will appear darker, because they were exposed to x-rays more.

I am new to this stuff. Please help. Thank you.

submitted by /u/lolomghelp
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Does improving certain mental abilities limit others similar to how physical abilities do?

Posted: 06 Jul 2020 10:29 PM PDT

A professional marathon runner is never going to be the weightlifting world champion, but is a professional chess player limited at language learning for example?

I hope the flair fits.

submitted by /u/loloman333
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Can electricity flowing through C4 set it off?

Posted: 06 Jul 2020 12:43 PM PDT

How do scientists estimate how long an extinct species lived?

Posted: 06 Jul 2020 01:55 PM PDT

For example, H. erectus is said to have lived between 1.89 million and 110,000 years ago (thus the species survived for more than 1 million years)

H. neanderthalensis is said to have lived between 400,000 - 40,000 years ago (thus their species lived for about 350 ky).

How exactly do we know how long their species survived?

submitted by /u/JSBach1995
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How do epidemiologists study viral transmission rates under various conditions?

Posted: 06 Jul 2020 03:16 PM PDT

I'm unclear about how viral transmission rates can be accurately studied mostly because it seems difficult for people to report exactly how they contracted a virus. Not saying I'm doubting them, just wondering how they do it.

Is it simply based on self-report? For example, Covid seems to be quite difficult to transmit outdoors with appropriate precautions. There was a study done in Wuhan that showed out of thousands of Covid contractions, only one occurred outdoors - how are they able to estimate that? How is it that we know that those who contracted it did so at whatever indoor event rather than some random outdoor interaction?

submitted by /u/NPDoc
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Since there are always new land masses being formed in the ocean, will the earth after billions of years become predominantly land?

Posted: 06 Jul 2020 09:49 AM PDT