Official "Science News" Thread

[science_man_88]

Originally Posted by ewmayer

3,000 miles ... 'That takes time'. Would 150,000 years qualify as 'sufficient time' in the intended sense? That's around 10,000 generations, i.e. - noting that of course people don't diffuse in a regular way like this - the technology would need to advance north a mere half-kilometer each generation, on average.

or about 528 yards a generation. 106 feet per year.

[rogue]

From a Baby’s Cry to Goethe’s Faust

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Do Brain Waves Conduct Neural Activity Like a Symphony?

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Strange waves rippled around the world, and nobody knows why

Your Dog May Not Be a Genius, after All

Wriggly, Giggle, Puffball: What Makes Some Words Funny?

Stabilizers, Fixers, Independents, & Organizers

[ewmayer]

o A Pond-Dwelling Virus Just Cured a Man's Antibiotic-Resistant Infection | Futurism -- bacteriophage therapy. See this ensuing discussion on Naked Capitalism, which provides both links for further reading and a major caveat, namely that phages can also act as a means for bacteria to exchange virulence (and presumably, resistance) factors.

o Book Review: Evolutionary Psychopathology - Slate Star Codex -- An interesting reader comment: "My anecdata to support the hypothesis: An ex had borderline personality disorder, and it was most likely caused/brought out by childhood abuse. I could see an evolutionary purpose to the psyche adapting to such conditions by favoring aggression as the coping strategy for survival in future relationships. Vulnerability would be too risky an approach, as the psyche was taught early on that it will not be permitted."

o New Metal-Air Transistor Replaces Semiconductors - IEEE Spectrum

It is widely predicted that the doubling of silicon transistors per unit area every two years will come to an end around 2025 as the technology reaches its physical limits. But researchers at RMIT University in Melbourne, Australia, believe a metal-based field emission air channel transistor (ACT) they have developed could maintain transistor doubling for another two decades.

The ACT device eliminates the need for semiconductors. Instead, it uses two in-plane symmetric metal electrodes (source and drain) separated by an air gap of less than 35 nanometers, and a bottom metal gate to tune the field emission. The nanoscale air gap is less than the mean-free path of electrons in air, hence electrons can travel through air under room temperature without scattering.

“Unlike conventional transistors that have to sit in silicon bulk, our device is a bottom-to-top fabrication approach starting with a substrate. This enables us to build fully 3D transistor networks, if we can define optimum air gaps,” says Shruti Nirantar, lead author of a paper on the new transistor published this month in Nano Letters. “This means we can stop pursuing miniaturization, and instead focus on compact 3D architecture, allowing more transistors per unit volume.”

Using metal and air in place of semiconductors for the main components of the transistor has a number of other advantages, says Nirantar, a Ph.D. candidate in RMIT’s Functional Materials and Microsystems Research Group. Fabrication becomes essentially a single-step process of laying down the emitter and collector and defining the air gap. And though standard silicon fabrication processes are employed in producing ACTs, the number of processing steps are far fewer, given that doping, thermal processing, oxidation, and silicide formation are unnecessary. Consequently, production costs should be cut significantly.

In addition, replacing silicon with metal means these ACT devices can be fabricated on any dielectric surface, provided the underlying substrate allows effective modulation of emission current from source to drain with a bottom-gate field.

“Devices can be built on ultrathin glass, plastics, and elastomers,” says Nirantar. “So they could be used in flexible and wearable technologies.”

Replacing the solid-channel transistors in space circuitry is another potential application. Because the electrons flow between the electrodes just as well in a vacuum (think vacuum tube) as in air, radiation will not modulate channel properties, making ACT devices suitable for use in extreme radiation environments and space.

Theoretical switching speeds in the multi-terahertz range ... yowza.

[ewmayer]

o These ants decorate their homes with the heads of their enemies | National Geographic

o New study explains creation of deadly California "firenado" | AP News

o Four small cities may have played an outsize role in spreading deadly flu | Science -- Interesting. So one doesn't need a huge petri dish (major metropolis), merely one that has the right combination of big-enough-ness and "fortuitous" exposure timing to incubate a virulent strain and then provide enough infected people to fuel a wider-scale breakout.

[tServo]

Originally Posted by ewmayer

o These ants decorate their homes with the heads of their enemies | National Geographic

The horror. The horror.

[Dr Sardonicus]

Originally Posted by ewmayer

o These ants decorate their homes with the heads of their enemies | National Geographic

Florida. Why am I not surprised? The chemical mimicry of those little automatons is pretty amazing. And then, using an irritating chemical to neutralize their opponents' heavier weaponry. Sort of like bringing pepper spray to a sword fight.

Hmm... (looks up recent goings-on in Florida's wildlife arena).

Hey! Screwworm flies made a comeback in 2016! Those little devils would give ranchers some sleepless nights. Luckily, they have an Achilles' heel, which I leave to the interested reader to look up.

[ewmayer]

Originally Posted by tServo

The horror. The horror.

Yes - warfare among the insects is about as brutal as it gets. They can't be bargained with. They can't be reasoned with. They don't feel pity, or remorse, or fear. And they absolutely will not stop... ever, until you are dead!

[Dr Sardonicus]

Originally Posted by ewmayer

Yes - warfare among the insects is about as brutal as it gets. They can't be bargained with. They can't be reasoned with. They don't feel pity, or remorse, or fear. And they absolutely will not stop... ever, until you are dead!

And, even when we exterminate them -- they'll be back!

[ewmayer]

Originally Posted by Dr Sardonicus

And, even when we exterminate them -- they'll be back!

Speaking of Ahhhnold - during childhood hikes in Austria, one of the fun things to do was to look for the large (often over a foot high) anthills one of the common local forest ant species there builds from piled-up evergreen needles. If you gently whapped the surface of such a pile with your open palm, hundreds of half-inch-long workers would rush to the surface, point their nethers at the 'intruder' and emit silk-thread-thin sprays of formic acid - we would try to have the sunlight shining on the mound from the opposite side so as to better see the acid streams. The smell is actually quite refreshingly bracing, in an I-was-a-victim-of-ant-chemical-warfare kind of way.

===============

o A 4,900-Year-Old Case of Plague in Sweden, Found in Teeth - The Atlantic

The troublesome teeth belonged to a woman buried in Sweden. She lived 4,900 years ago, and she died young. Archaeologists found her at the turn of the last millennium, her bones jumbled up with dozens of others in a limestone tomb. Geneticists sequenced her DNA a few years ago, revealing her to be, unsurprisingly, one of the Neolithic farmers who occupied Europe at the time.

Only when scientists reexamined DNA from two of her teeth last year did they notice something shocking: Her DNA was in there all right, but so were genetic sequences from Yersinia pestis, the bacterium that causes plague. The plague is known to have swept through Europe in later times—most infamously as the Black Death during the Middle Ages. But scientists thought the disease had originated thousands of miles away in Asia. What was it doing this far west, in Sweden, this long ago?

“It was really unexpected,” says Nicolás Rascovan, a genetics researcher at Aix Marseille Université. The answer, he and his co-authors suggest in a new study, is that the plague actually originated in Europe. And the bacteria from the woman’s teeth might be the earliest evidence of a continent-wide epidemic, one that explains a sudden and mysterious collapse in the European population.

The data-mining aspects of this are really cool - 95-99% of a typical such DNA sample has been getting discarded due to its non-human-ness. But in many of not most cases that until-recently-ignored stuff actually tells a crucial tale.

o On the junk-science front, a brutal takedown of a dietary study:

The Truth About Low-Protein, High-Carb Diets and Brain Aging | Psychology Today

o And on a lighter note, it seems there are animal analogues of schoolchildren who stick pencils and such up their noses just because they can:

‘Make better choices’: Endangered Hawaiian monk seals keep getting eels stuck up their noses and scientists want them to stop | Washington Post. A reader comments: "A species even stupider than humans."

It's enough to move one to song: If you see a big eel / up the nose of a seal / that's a moray...

[GP2]

Originally Posted by ewmayer

Yes - warfare among the insects is about as brutal as it gets. They can't be bargained with. They can't be reasoned with. They don't feel pity, or remorse, or fear. And they absolutely will not stop... ever, until you are dead!

On that note, see if you can bear to watch this 200-proof nightmare fuel right to the end:

https://www.youtube.com/watch?v=rwPaUma6R_k

Props to the foley artist.

[Dr Sardonicus]

Originally Posted by ewmayer

Speaking of Ahhhnold - during childhood hikes in Austria, one of the fun things to do was to look for the large (often over a foot high) anthills one of the common local forest ant species there builds from piled-up evergreen needles. If you gently whapped the surface of such a pile with your open palm, hundreds of half-inch-long workers would rush to the surface, point their nethers at the 'intruder' and emit silk-thread-thin sprays of formic acid - we would try to have the sunlight shining on the mound from the opposite side so as to better see the acid streams. The smell is actually quite refreshingly bracing, in an I-was-a-victim-of-ant-chemical-warfare kind of way. <snip>

Half-inch long ants -- that's pretty impressive! Carpenter ants come to mind. They can bite, but AFAIK they don't spray.

There's an alien species here in the USA which I've never personally encountered that isn't that big, but by all accounts you do not want to mess with -- fire ants. They don't spray either -- they just attack en masse. A native species in drier parts of the country you also do not want to tangle with are harvester ants. Their anthills (which can grow impressively large over the years) look like piles of coarse sand, with an area around them devoid of any vegetation. (I'm not sure whether they use formic acid as an herbicide. I believe some rain forest species of ants do.) They too attack intruders vigorously, biting and stinging. I have heard of people with multiple harvester ant colonies on their property using a shovel to conduct a "cultural exchange program" between different colonies. The "exchange students" do not fare well.