Random Science News Thread

[Cord Hurn]

+JMJ+


NBC News @NBCNews | Twitter



--> --> Maybe 'dark matter' doesn't exist after all, new research suggests [In-Depth]

Thank goodness we're not on some kind of tight timetable to figure all of this out!

[Wosbald]

+JMJ+

Infected after 5 minutes, from 20 feet away: South Korea study shows coronavirus’ spread indoors [In-Depth]

An outdoor dining set-up with hand sanitizers and stuffed bears to enforce social distancing in Seoul. (Lee Jin-man / Associated Press)


Dr. Lee Ju-hyung has largely avoided restaurants in recent months, but on the few occasions he’s dined out, he’s developed a strange, if sensible, habit: whipping out a small anemometer to check the airflow.

It’s a precaution he has been taking since a June experiment in which he and colleagues re-created the conditions at a restaurant in Jeonju, a city in southwestern South Korea, where diners contracted the coronavirus from an out-of-town visitor. Among them was a high school student who became infected after five minutes of exposure from more than 20 feet away.

The results of the study, for which Lee and other epidemiologists enlisted the help of an engineer who specializes in aerodynamics, were published last week in the Journal of Korean Medical Science. The conclusions raised concerns that the widely accepted standard of six feet of social distance may not be far enough to keep people safe.

The study — adding to a growing body of evidence on airborne transmission of the virus — highlighted how South Korea’s meticulous and often invasive contact tracing regime has enabled researchers to closely track how the virus moves through populations.

“In this outbreak, the distances between infector and infected persons were … farther than the generally accepted 2 meter [6.6-foot] droplet transmission range,” the study’s authors wrote. “The guidelines on quarantine and epidemiological investigation must be updated to reflect these factors for control and prevention of COVID-19.”



People wearing face masks walk under a banner emphasizing an enhanced social distancing campaign in front of Seoul City Hall. The banner reads: “We have to stop before COVID-19 stops everything.”(Ahn Young-joon / Associated Press)


KJ Seung, an infectious disease expert and chief of strategy and policy for the nonprofit Partners in Health’s Massachusetts COVID response, said the study was a reminder of the risk of indoor transmission as many nations hunker down for the winter. The official definition of a “close contact” — 15 minutes, within six feet — isn’t foolproof.

[…]

Lee, a professor at the Jeonbuk National University Medical School who has also been helping local authorities carry out epidemiological investigations, went to the restaurant and was surprised by how far the two [case studies] had been sitting [at the restaurant implicated at the center of the study]. CCTV recordings showed the two never spoke, or touched any surfaces in common — door handles, cups or cutlery. From the sway of a light fixture, he could tell the air conditioning unit in the ceiling was on at the time.



Diagram of the outbreak at a South Korean restaurant equipped with ceiling-type air conditioners: arrows represent the air flow. Curved air streamlines represent where air is reflected off a wall or barrier, and moves downward toward the floor.(Korean Academy of Medical Sciences)


Lee and his team re-created the conditions in the restaurant — researchers sat at tables as stand-ins — and measured the airflow. The high school student and a third diner who was infected had been sitting directly along the flow of air from an air conditioner; other diners who had their back to the airflow were not infected. Through genome sequencing, the team confirmed the three patients’ virus genomic types matched.

“Incredibly, despite sitting a far distance away, the airflow came down the wall and created a valley of wind. People who were along that line were infected,” Lee said. “We concluded this was a droplet transmission, and beyond” 6.6 feet.

The pattern of infection in the restaurant showed it was transmission through small droplets or larger aerosols either landing on the face or being breathed in, said Marr, the Virginia Tech professor who was not involved in the study. The measured air velocity in the restaurant, which did not have windows or a ventilation system, was about 3.3 feet per second, the equivalent of a blowing fan.

“Eating indoors at a restaurant is one of the riskiest things you can do in a pandemic,” she said. “Even if there is distancing, as this shows and other studies show, the distancing is not enough.”

The study was published at a time when South Korea, like many other countries, is on edge amid a new wave of coronavirus infections, with daily case rates hovering around 600 in recent days. Seoul, the capital, this week began requiring restaurants to close by 9 p.m., limiting coffee shops to takeout only and forcing clubs and karaoke bars to shut down.

[…]

[samrw3]

Airless titanium tires - built for NASA coming to bikes and who knows where in years.

https://www.msn.com/en-us/travel/news/n ... ocid=ientp

[peter]

Apparently the standard model received another blow to its solar plexus recently with the evidence that certain muons under investigation did not exhibit the correct degree of magmatism predicted by the model (or something like this). If the results are confirmed then it could further undermine the models validity (which I believe is looking pretty shaky already) and instigate the search for new particles and answers.

[peter]

Just been looking at a Guardian article on this new hominid skull (the Harbin skull) found in China some ninety years ago, but hidden in a well to protect it from the Japanese invaders of the time and remaining undisclosed in situ ever since.

The skull is exiting not just because of its extraordinary state of preservation, but also because of its mix of older and more modern features that would seem to confirm the existence of a third line of human development alongside that of modern man and neanderthal man - and one that sits closer to us than even did the Neanderthals.

Of course, as with all things paleoanthropological (what a word!) it is somewhat unclear as to how significant this find is, and workers elsewhere from the team of Chinese anthropologists (which includes the Professor of Anthropology at the British Museum of Natural History, on loan as it were) who are studying the skull the feeling is that it is early days to be giving the skull the status of being named as a new branch on the tree of human ancestry. Indeed some feel that the skull is quite possibly of the Devonian (Devonisian?) type, a mysterious branch of hominid postulated from finds made in Siberia. The problem is that the fossil record is so fragmentary, and the variation between individuals of the same species/type so great (we can see this from ourselves) that it becomes a murky game of chance indeed, to attempt to put any realistic divisions between the specimens we have at our disposal. Safe to say that at the time we are talking about, there were possibly around ten types of closely related human sub-types extant - and then we came out of Africa and according to our nature killed them all. A sobering thought that tells us much about who we are, does it not?

[Rigel]

That's cool. How strong is the evidence for a third line or group of (more-or-less) modern humans, rather than just the inter-breeding of sapiens and neandertalis that we've been reading about for the last few years?

[peter]

From the article I read Rigel, it's certainly building and this skull, though not actually nailing it down, goes a long way toward doing so. Depending upon the scientific consensus that develops (and everything in the field of paleoanthropology is dependent upon the consensus of majority opinion - same in all branches of science I guess), the find could be the one that brings the 'third line' hypothesis to the point where it is accepted as the most likely correct.

But.......there is a tremendous amount of professional jealousy in this field - read Donald Johansson's account of the fight he had with the Leakey's to get Lucy recognised to see how bad it can get - and this can really obscure and even direct the course of where the consensus opinion lies. There are powerful academic bodies who fight savagely to protect their own status at the top of the pile, and who deeply resent any suggestion that might lower the significance of their own work (in terms of position in relation to closeness to the human line), and they will not be happy about the emergence of anything that does so. (The ultimate alpha position is to have the fossil that is closest to modern man on the actual line of development that leads directly to him - not suggested as being the case with this fossil, but it's still a highly prestigious find if it confirms the three line approach.) Those whose research is concentrated upon the Neanderthal fossils will not want to see their man shunted into third place and will mount a significant defense against this happening. Remember - allocation of resources and money depends upon such opinions - and people's jobs hang on them. This is always a factor in science, and has far more influence on what goes on - and what is accepted as scientific truth - than most practitioner's would care to admit.

[Avatar]

Safe to say that at the time we are talking about, there were possibly around ten types of closely related human sub-types extant - and then we came out of Africa and according to our nature killed them all. A sobering thought that tells us much about who we are, does it not?

Ex Africa Aliquid Novii.

1) I feel it only fair to point out that if we did, all of those branches would likely have gladly done the same. That is indeed the "nature" of "nature." The successful survive.

2) Given how much Neandertal DNA we're supposed to still be carrying around, killing them all is only one possibility. We probably killed some, were killed by others, and impregnated anything that was genetically compatible enough to be impregnated.

We were coming out of Africa about 55,000 years ago, as a relatively small population, maybe as few as 5,000-10,000 individuals during the "genetic bottleneck."

More than enough time to have incorporated other branches into our own descents I'm sure.

--A

[peter]

Absolutely Av. It seems to me that it is certainly a case of man just doing what man does. We don't appear much different in our treatment of each other today (when our thin veneer of civilization is stripped away) and it would not be sensible to expect any difference in the kill or be killed world of 100,000 years ago.

But the idea of all of these different sub-types is interesting to me, coming as I do from the school of understanding that the defining characteristic of the species as a unit of classification is the ability to interbreed and produce fertile offspring. (That last is very important, because it screens out all the production of mules which is commonly seen in the crossbreeding of closely related species.) So if we were able to interbreed with these ten or so other 'types' (producing said fertile offspring) then they were by definition off the same species as us anyway. So we are really back to where we started - simply man killing man.

That we had the hubris to designate ourselves Homo sapiens (wise man) seems laughable to me; better Homo occisor perhaps?

[Avatar]

Homo superstes perhaps...

--A

[peter]

An admirable compromise Av. Let it be so!

[Hashi Lebwohl]

We were coming out of Africa about 55,000 years ago, as a relatively small population, maybe as few as 5,000-10,000 individuals during the "genetic bottleneck."

The genetic bottleneck which led to modern humans happened about 70,000 years ago when the supervolcano Toba erupted. The date is an approximation based on the mutation rate of mitochondrial DNA.

I also strongly suspect that pre-historic humanity was much more technologically advanced than we think they were. Sadly, geological processes--mostly ersion by glaciers or floods as the glaciers melted--has erased almost all that evidence. This explains how they were able to construct megalithic buildings, especially in places in South America--how, exactly, does one get a 50-ton piece of stone up a mountain?

[peter]

how, exactly, does one get a 50-ton piece of stone up a mountain?

Muscle - lot's of muscle!

[Hashi Lebwohl]

how, exactly, does one get a 50-ton piece of stone up a mountain?

Muscle - lot's of muscle!

Telekinesis, or possibly magic.

Alternatively, there could be some chemical process by which one forms a clay body so that when heat is applied to it is sets into stone....but we probably would have rediscovered such a technology by now.

[Rigel]

Alternatively, there could be some chemical process by which one forms a clay body so that when heat is applied to it is sets into stone....but we probably would have rediscovered such a technology by now.

I dunno, we still can't recreate Roman cement (although we're getting closer; apparently a big piece of the puzzle was the fact that seawater, over time, changes the composition of the cement, so what we see today isn't what the Romans poured).

[Fist and Faith]

That's pretty cool.

[peter]

I don't know; I am certain that some technical processes were more advanced in the past and that these skills have been lost (flint knapping would be a good example), but I'm not sure that I go for the idea of a seriously advanced civilization/culture that for some reason was blown back into the stone age at some time deep in our past. Rather I think, we may have at times (and in limited places) achieved levels of mental insight, that thought may have taken us into deeper places in terms of understanding of our place in the universe etc; insights that might engender wisdom and harmonious ways of living (witness the Asmat tribe of Papua New Guinea or the Orang-asti of Malaysia), but would do nothing to protect you against men with clubs and spears.

In respect of the technically advanced idea; the building of megalithic structures is of itself not terribly difficult. I believe that the Egyptians only had limited abilities with mathematics and certainly the architects of the Gothic cathedrals even, did not employ advanced mathematics in the process as such. Yes the problem of getting huge chunks of stone up the steep sides of mountains is difficult - but not intractable. Time and limited engineering, alongside huge availability of expendable manpower will do the trick. But I find it difficult to accept that such advanced technological civilization as we might conjecture could dissapear without trace of other engineering achievement being left alongside the huge building works we see today.

[Avatar]

Largely agree Peter. Certainly techniques have been lost. However, in fairness to Hashi, he did say that they may have been more technologically advanced than we think they were, not more advanced than we are.

--A

[Hashi Lebwohl]

Exactly. The Baghdad Battery proves that they could had had rudimentary electricity in small or simple circuits, but they might not necessarily have known what to do with it other than "medical applications". They certainly did not have any sort of large generation capability. The Aeliopile proved the concept of steam power...but Ancient Greeks did not have even steam-driven water pumps, so no advancements down that path.

[Rigel]

mRNA flu vaccines! Bundled with COVID, RSV and HMPV!

I was wondering when we'd see this...

We won't be seeing it this year - there's no emergency use authorization, unlike the COVID vaccine - but this could be huge for public health. Current vaccines for the flu are sometimes as low as 40% effective, and a lot of people can't even take them because of egg allergies... imagine if the efficacy were as high as the COVID vaccine, around 90%!