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Note that the spread was predominantly along trade routes. While there is decent evidence supporting the use of (black plague) bodies (which, btw. were already spreading in Asia and the Middle East), the entry of the plague was likely independent of that (or it may have contributed it, but was not the major driver). The narrative of the use of cadavers and the spread of the bubonic plague to Europe following the the siege of Caffa was strongly based on the account by Gabriele de' Mussi. Historians disagree whether he was actually physically present during the siege, but it appears that they think it is at least plausible that cadavers were hurled into the city. There is also the possibility that the plague arrived with the army and was subsequent transmitted by rodents, but despite overall uncertainties it is (from what I have read) not the favoured explanation. In the accounts de' Mussi also said that those escaped from Caffa were bound to Genoa Venice and so on and thereby spread the disease. However that clashes with what I think is now fairly well established understanding how the plague spread into Europe. It is well established that the plague spread over the Crimea, but cases in Genoa and Venice appeared well over 2 years after the siege of Caffa. Since even under unfavourable conditions the voyage should have not taken more than a few months, the timeline does not line up well. Another aspect that even if that timeline would have worked out, the time required would still have resulted in a substantial outbreak on the ships themselves. But again, around that time, there were no records of something that must have been considered to be a significant event. There are also folks who dispute that corpses were used in the first place (as there are no reports from folks fleeing from Caffa describing it aside from de' Mussi's account) or that there is no indication that it was knowingly used as a bioweapon (some dispute that bodies would be effective, they should have flung rats instead...). There is for example the speculation that the plague may have entered Caffa via the waterways. The Mongols were not able to fully block those and this where Caffa was getting resupplied. Also historians report that a step-wise entry of the plague into Europe is more likely which makes a spread over trade routes via Crimean ports even more likely. Well established reports pinpoint spring 1347 as the start of the plague in Constantinople, for example. I.e. there are quite a few reports that contradict the strong narrative of warfare-mediated spread, which is quite fascinating actually as not only historians have been working on it, but also epidemiologists and microbiologist, who use the documents to establish timelines and spread, not dissimilar to modern epi-studies (just with scarcer data). What is rather neat is that a fairly recent PNAS paper actually described genome evolution in Yersinia pestis which is consistent with repeated introduction via migratory and trading routes.

Somewhat too simplistic to be helpful? Perhaps I'm being a hypochondriac, but I'm rather concerned that every time I run for a bus in inclement weather I come down with all the symptoms of coronavirus.

We can go that way. I had been thinking a comedic level of incompetence, where the protagonists inadvertently infect the people at the top of the terrorist organization, and think that drinking Corona beer (it’s the Corona virus, dude!) makes them more dangerous They fail to kill anyone at their target, which is supposed to be an old folks home but they end up at a military base with a similar name (they’re drunk on Corona), and nobody dies because they salute rather than shake hands and are young and healthy.

Here is my opinion after thinking about the above. I can definitely see @studiot's point of view, it is very familiar to me from some of my attempts at providing answers here on the forum. But personally I do often find that the interesting but badly stated questions are triggering me to think outside the box. My attempts at figuring out the question is often contributing to enhancing my knowledge just as much as my tries to provide an answer. But I think that those discussions are sometimes (often?) not very interesting for others to follow so in the general case it may not add much value to the site even if I personally enjoy that kind of topics. I have some vague idea about some kind of a "questions about questions" or "help me improve my question" or "How would a scientist ask"-section where one could submit a vague question and get help to enhance the question it until it can be properly addressed from a scientific point of view. "Bad" question could be moved to that section until "good enough". But I'm not sure it will help. Those in need of the section may be offended by a move or be discouraged from further questions. And it maybe it adds unnecessary work for moderators to move stuff around.

Chronic coughing would seem the most concerning.

Ah, OK. I hadn't noticed the bolded part. My mistake; carry on.

I was gonna give you a +1 for being witty, JC. Then I realized that you had used the chemical name for hydrogen peroxide, instead of water. You blew it ! Oh well, you'll have to settle for a consolation prize ( +1 )

...and hydrogen dioxide...get in your lungs and you can't breath...often fatal...and the government sprays the stuff on the streets and public vehicles

That is indeed a cause for concern. And to me, nationalism and unilateralism are going to make things worse. It should be noted that the graphs are specifically to spread awareness regarding COVID-19. Coronavirus while all respiratory (to my knowledge) can have different suites of symptoms. The discussion with cold is complicated by the fact as it is not a specific disease (as e.g. COVID-19) but rather a descriptor of symptoms that can be caused by a number of viruses and some of them belong to the family of coronaviruses. A number are endemic and responsible for a significant fraction of upper respiratory infections. Up until SARS, they were considered mostly harmless and often symptoms would fall under the "cold" bracket.

The times it takes to stop the objects are related as their masses: [math]m_{1}/m_{2}[/math] Since question is not very clear I do some assumptions there are two objects [math]m_{1}[/math] and [math]m_{2}[/math] where mass of [math]m_{1}[/math] < mass of [math]m_{2}[/math] at time [math]t_{0}[/math]=0 [math]m_{1}[/math] and [math]m_{2}[/math]are accelerated from rest with acceleration a. at time [math]t_{1}[/math] acceleration of [math]m_{1}[/math] and [math]m_{2}[/math] stops at time [math]t_{2}[/math] some kind of force F starts to affect [math]m_{1}[/math] and [math]m_{2}[/math]. Force [math]F[/math] is acting in opposite direction of movement of [math]m_{1}[/math] and [math]m_{2}[/math] Force [math]F[/math] acts independently on [math]m_{1}[/math] and [math]m_{2}[/math] until each object have stopped. Newtonian physics applies (low speeds, solid bodies) Apply some math: velocity [math]v[/math] for both objects [math]m_{1}[/math] and [math]m_{2}[/math] at time [math]t_{1}[/math] is then [math]v=a*t_{1}[/math] momentum at [math]t_{1}[/math] is [math]p_{1}=m_{1}*v[/math] and [math]p_{2}=m_{2}*v[/math] Impulse = change in momentum Force F is applied until objects are stopped, that means change of momentum is [math]p_{1}[/math] and [math]p_{2}[/math] for [math]m_{1}[/math] and [math]m_{2}[/math] If we label time to stop [math]m_{1}=t_{s1}[/math] and time to stop [math]m_{2}=t_{s2}[/math] then [math]t_{s1}=p_{1}/F=m_{1}*v/F[/math] [math]t_{s2}=p_{2}/F=m_{2}*v/F[/math] Result: [math]\frac{t_{s1}}{t_{s2}}=\frac{m_{1}}{m_{2}}[/math]

I think there are two slightly different factors here. Firstly, we know that CO, CO2 (or water or table salt) are not elemental because they can be broken down into, or synthesized from, their constituent parts. (We also know that their constituent parts are elemental, because they cannot be broken down or synthesized from other atoms). The other important point is that the component parts only combine in simple integer ratios. This tells us two things: that the compounds are not just simple mixtures of carbon and oxygen. There isn't a mixture that is half way between CO and CO2, with intermediate properties, for example. Also, just mixing C and O in those proportions does not lead to the compound. There needs to be a reaction (with the release, or absorption, of energy). A mixture of two parts hydrogen to one part oxygen is not water, it is just a mixture of hydrogen and oxygen. I guess one could (with effort) come up with an explanation of these facts based on an assumption that carbon and oxygen are continuous elemental substances that are infinitely divisible, but still always combine in constant ratios (and with a minimum quantity). But it is much simpler to explain it in terms of them being made up of particles that can only combine with a fixed number of other particles. In Dalton's time, you could perhaps argue that this atomic theory was just a hypothesis. But then the model was developed further (with valence electrons to explain the number of other atoms that an atom can combine with, and so on) and now we able to manipulate and image individual atoms. (And even split them, despite their "atomic" or elemental nature.)

Technically the virion refers to a whole virus particle. Practically it is the same as a single (complete) virus but it is typically used in structural context. Also just to be sure: the causative agent of flu are influenza viruses. These include members of Swine and bird flu for example belong all to the group of influenza viruses (classification are provided in Studiot's link). COVID-19 is a specific disease caused by the strain SARS-COV2, which belongs to the family of coronaviruses. Other notable diseases associated with members of this family include SARS and MERS.

If you get tired of marking student papers, you have a future as a screenwriter. Recently read statistics that 0.2% of infected people under 40 yrs age have died. But for those 80 yrs and up the fatality rate is over 20%. Meanwhile I have a sniffling, sore throat cold, due to the constant temperature changes this time of year ( and not dressing appropriately ), and I can't go out lest people think I have the COVID-19 scourge.

The plot revolves around a group of highly trained professionals who break into homes of elderly folks and aggressively cough into their faces for a few minutes. In a heartwarming twist one of their presumptuous victims confuses the terrorist with their grandchild to whom she had lost contact. After a furious intermezzo consisting of baking and copious amount tea the terrorist realizes that deep inside he is just longing for the love of a family. Meanwhile the grandparent realizes that the nightly visitor in stealth suit is indeed not her grandchild (the climbing hook on the balcony being a crucial hint- as well as a flashback highlight that the real grandchild had a fear of heights). But she enjoys the moment too much to care.Tragically, this human moment is also what ultimately resulted in successful infection. The terrorist becomes guilt-ridden when it becomes clear that the lonely grandma is not long for this world and he tries to reach her a last time to say his farewells. Meanwhile, his terrorist buddies consider him a traitor and try to stop him resulting in a highly choreographed fight scene involving lots of offensive coughing and running noses in slow-mo (the filmmakers did not consult experts as per usual and did not realize that this is not part of the symptoms). Finally, he survives all these ordeals and reaches the grandma, who turns out to be a special CDC/Homeland security agent in disguise (Jason Stratham) who have been delaying a rollout of coronavirus testing in favour of sting operations to catch corona-terrorists. PS: can anyone tell that I really, really do not want to read those student reports?

Well, if you wanted to actually kill someone with the coronavirus you'd have to try to sneak into homes for the elderly to be efficient. Assuming you get in contact with 100 folks above 80 you may have caused somewhere between 8-14 fatalities. You could contribute to overall spread, but if it is already spreading as it is now, it is unclear whether it would amount to more. But to do so, you will have to spend significant time with each person as casual contact seems to inefficient. So in other words you may have made the situation worse, but it is unclear how much you contributed. That, is typically just the opposite of what most lone wolf types have in mind. Part of their motivation is some distorted desire for notoriety and striking fear into folks. A "regular" mass shooting or other attack is likely to be more satisfying to them. On top, this is only likely going to work during an ongoing outbreak as there is a decent likelihood for vaccines eventually and/or most folks will develop immunity (due to infection). So all they are doing is accelerating things perhaps a little bit. Perhaps worse than any of that, poor public health responses are likely to create more fatalities than any level of deliberate act of terrorism is going to achieve. Think about that for a minute. Let's say hypothetically that testing for the virus is going to cost more than you can afford and you have the choice between going to work or lose the job, what do yo do? You cannot self-quarantine since you live paycheck to paycheck and have no food stocked up because of that. How many are in that situation compared to say ten deliberate spreaders? Now combine that with a slow roll out of tests even if they are affordable.

Hi guys, I am in sunny California where oranges grow on trees in people's yards and evidently it never really rains! I flew out here to see my son and grandchild and help them get their house upacked and set up. My dad died days before I arrived andIfound out I had inherited al of his properties... Sort of... But he didn't leave a will so everything is in "probate" and all his properties will be sold to settle his debts and I have to make sure this gets done. I named my son executor of his estate, my son volunteered btw. I feel like I went on vacation only to find the sword of damacles floating over my head. Fun fun in sunny CA!

Looks like typical choloroform/phenol extraction protocol. I have not experienced myself but in general there a couple of theoretical effects that one might need to control to make sure that good phase separation happens. This includes having enough ionic strength of the aqueous layer, control of pH or sometimes even just the addition of another organic solvent. I suspect that bad phase separation can happen due to excess amounts of compounds that in a given poorly separate into either phase, which includes certain proteins and lipids.

Must be due to the elevated shipping costs for sending to isolated tribes out there.

The Lorentz-Poincare interpretation of special relativity is not my pet theory, but was the only interpretation of SR from 1905-1909, until Minkowski proposed his spacetime interpretation in 1909. Before being banned forever for mentioning this triviality again, I would suggest the adminstration of the forum how to handle the original interpretation of SR, as proposed by Lorentz and Poincare, which is usually named "Lorentz ether", and those who follow the recommendations given by Bell in Bell, J.S. (1976). How to teach special relativity. Progress in Scientific Culture 1(2), reprinted in Speakable and Unspeakable in Quantum Mechanics where he suggests to teach also this traditional approach to relativity because it gives the people better intuitions. Some forums decide to ban discussions of the Lorentz ether as anathema. In this forum, it was suggested that it is possible to discuss it, but in reality I was banned for doing it. I think banning people for doing things not explicitly forbidden is much worse than explicitly forbidding whatever theories of physics the admins don't like. That's fine with me, I have, of course, my own opinion about the scientific value of such rules, but I accept the right of the administration of the forum to forbid whatever they don't like. But not to forbid it in the rules, but then banning people in reality, naming the Lorentz-Poincare interpretation a personal pet theory, ... Just to clarify how I see the actual situation: There are threads for discussing my "pet theories", namely my generalization of the Lorentz ether to gravity and my ether model of the SM. And there is the Lorentz ether, as the classical interpretation of SR, which is not my pet theory. Therefore I think that I'm allowed to discuss it in every thread about relativity, if it gives some other perspective which may be interesting for some readers. I do this following the recommendations made Bell, thus, I follow here an established mainstream scientist too, and I do not see any violation of the actually existing rules of the forum. So, please clarify the rules of this forum, regarding the discussion of the original interpretation of SR. Is it anathema or legitimate part of established science? Oh, I see the date is Friday. the 13th. So, the result of this posting is predictable - a ban forever. So, good buy.