Even though modern medicine has come a long way,
there are still a number of things we’re not very good at.
Chief among them: fixing brain injuries.
But a case study published this week in the journal
Current Biology might start to change that.
Because a group of French researchers took a patient
suffering from unresponsive wakefulness syndrome — what’s sometimes called a vegetative state —
and figured out how to make him responsive again.
Unresponsive wakefulness isn’t quite the same as a coma.
Instead of being asleep and unresponsive,
the patient is awake and unresponsive.
So their body is working fine,
but they’re not showing signs that they’re aware of anything.
The neurons in their brain just aren’t communicating with each other the way they should be.
Sometimes awareness can come back,
because the brain is pretty good at fixing itself.
But sometimes it doesn’t.
Scientists still aren’t sure exactly how
and why that works for some people and not for others.
But most will agree that after about a year of unresponsive wakefulness,
the chances of recovery are very, very slim.
So these researchers were trying to find a way to bring people back.
Earlier research has shown that
patients with minimal levels of consciousness improved a bit
when a certain nerve was stimulated,
so the team wondered if the same thing could
work for someone with even less awareness.
The patient in the study was a 35-year-old man
who’d been unresponsive for 15 years because of a car accident.
The researchers decided to try stimulating his vagus nerve,
one of the most important nerves in the body.
It sends signals from your brain to pretty much every other organ,
and is responsible for things like maintaining blood pressure, regulating mood,
and even making you feel drowsy after you eat too much.
It’s also very involved in keeping you alert and awake,
so the team wanted to see if stimulating it
electrically could help get the patient responsive again.
And … it worked.
After about a month of treatment,
the man actually started reacting to things.
He turned his head when someone asked him to.
He could follow movements with his eyes.
He even reacted with a sort of fear when one of
the researchers moved suddenly.
The results of this treatment are nothing short of incredible.
This guy was unresponsive for 15 years.
That said, this was only one case.
And most scientific conclusions need to be made with a few more than that.
The researchers say that
they want to test this on more patients in a similar state and
see if it helps them recover faster.
And if it does, doctors might someday have more options
when it comes to treating people stuck in unresponsive wakefulness.
In the meantime, other researchers have been
looking for new solutions to a totally different problem:
how to power our excessive electrical needs in a way that won’t make
climate change ten thousand million times worse.
Researchers from Columbia University have been
working on a new way to harness energy
from a process that’s happening somewhere around you right now.
And in a paper published this week in the journal Nature Communications,
they’ve shown that it might be way more powerful than they thought.
Every year, more than 500,000 cubic kilometers of water evaporates
从世界各地的海洋 湖泊 河流 小溪中蒸发出来
from the oceans, lakes, rivers, and creeks all over the world.
And when that much water changes from a liquid to a gas,
it uses an enormous amount of energy.
A few years ago, the researchers wondered if that energy could be
turned into a renewable source of power
— what they called an evaporation engine.
And in 2015, they developed some working prototypes.
Strangely, it’s all powered by a property of bacterial spores —
a kind of tough outer shell that bacteria form when conditions get rough.
The bacteria will sort of go to sleep and just chill there,
waiting for their environment to get better.
The researchers discovered that these spores will expand when you hydrate them
but then contract again when the water goes away.
When they put drops of the bacterial spores onto tape and dried them out,
the tape curled itself up,
and when they exposed the spores to humidity or moisture,
the tape expanded again.
In other words:
the spores were using the energy from evaporation to power movement.
There are a few versions of the evaporation engine.
One sits on top of a pool of water and uses natural
evaporation to move shutters back and forth.
Another uses differences in humidity to spin a turbine
and power a tiny lego car.
They’re super cute!
But the technology is seriously new
and hasn’t really had enough time to develop into something that can actually be used.
So in this week’s paper,
the team demonstrated the engine’s potential using math.
By developing new computer models that looked at how much water is available,
along with surface area information and meteorological data,
the researchers calculated that the technology could generate up to 325 gigawatts of power.
That’s 69% of the total power used in the United States in 2015,
which is huge.
They also calculated that from one reservoir in Texas,
they could get 178 megawatts of electricity a year.
That would be enough to power more than 130,000 homes.
That’s the best case scenario, though.
Covering an entire reservoir or lake with an evaporation engine has its drawbacks,
because covering water sources can dramatically change the chemistry of an ecosystem.
Plus, lots of bodies of water are really important for communities.
Who doesn’t want to picnic by the water and go out on the boat
and then you’re just in the shade of your weird evaporation engine.
But the evaporation engine could be useful
because it has an advantage over other forms of renewable energy.
Both wind and solar power rely on some sort of weather,
but the water cycle is always going on in the background.
So, give it some time and your lights could be powered by bacterial spores getting a little moist.
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