Removing all the dangerous bacteria from drinking water would have enormous health benefits for people around the world.
The technologies exist for doing that, but there’s a problem: cost.
Now MIT’s Rohit Karnik thinks he’s on to a much less expensive way to clean up water: Use the xylem of a plant.
Now if you remember your high school biology, you’ll know that xylem is the stuff in plants that transports water in the form of sap from the roots to the leaves.
"And the way the water is moved is by evaporation from the leaves," says Karnik.
It’s somewhat like what happens when you put a straw into a glass of liquid. Evaporation from the leaves has the same effect as sucking on the straw.
Pulling water up to the leaves this way creates a problem for the plant, but also an opportunity for an inventor.
The plant’s problem is something called cavitation, or the growth of air bubbles, which makes it harder for water to reach the leaves. But Karnik says xylem has a way of getting rid of these bubbles.
"The xylem has membranes with pores and other mechanisms by which bubbles are prevented from easily spreading and flowing in the xylem tissue," he says.
And it turns out these same pores that are so good at filtering out air bubbles are just the right size for filtering out nasty bacteria.
To prove it worked, he created a simple setup in his lab. He peeled the bark off a pine branch and took the sapwood underneath containing the xylem into a tube. He then sent a stream of water containing tiny particles through the tube and showed that the wood filter removed them.
"We also flowed in bacteria and showed we could filter out bacteria using the xylem," he says. Karnik estimates the xylem removed 99.9 percent of the bacteria.
The results were published Wednesday in the journal PLOS ONE.
Image: Making a xylem water filter is easy: Just peel back the bark and stick inside a tube. (PLOS ONE)
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Only big enough for a bunk bed surrounded by wire walls, these minuscule dwellings aren’t a project in urban microhousing. They’re the result of poor workers trying to find a place to live in the city’s booming real estate market.
(via fastcompany)Source: fastcodesign
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KUSA: Colorado collected $2.1 million in recreational marijuana taxes in January, the state Department of Revenue reported. These are the first tax figures for the first U.S. state to legalize retail marijuana.
Officials also reported the state brought in $1.4 million from medical marijuana.
Colorado legalized pot in 2012. In November, voters enacted the 15 percent excise tax and a 10 percent special sales tax on the drug, which is charged on top of ordinary sales tax.
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T he disappearance of a Malaysian airliner about an hour into a flight to Beijing is an “unprecedented mystery”, the civil aviation chief said on Monday, as a massive air and sea search now in its third day failed to find any trace of the plane or 239 people on board.
Dozens of ships and aircraft from 10 countries scoured the seas around Malaysia and south of Vietnam as questions mounted over possible security lapses and whether a bomb or hijacking attempt could have brought down the Boeing 777-200ER which took off from the Malaysian capital, Kuala Lumpur.
The area of the search would be widened from Tuesday, Azharuddin Abdul Rahman, the head of Malaysia’s Civil Aviation Authority, told reporters.
A senior police official told Reuters that people armed with explosives and carrying false identity papers had tried to fly out of Kuala Lumpur in the past, and that current investigations were focused on two passengers who were on the missing plane with stolen passports.
"We have stopped men with false or stolen passports and carrying explosives, who have tried to get past KLIA (airport) security and get on to a plane," he said. "There have been two or three incidents, but I will not divulge the details."
Interpol confirmed on Sunday at least two passengers used stolen passports and said it was checking whether others aboard had used false identity documents.
Azharuddin said a hijacking attempt could not be ruled out as investigators explore all theories for the loss of Malaysia Airlines Flight MH370.
"Unfortunately we have not found anything that appears to be objects from the aircraft, let alone the aircraft," he told a news conference. "As far as we are concerned, we have to find the aircraft. We have to find a piece of the aircraft if possible."
Azharuddin also said the two men with stolen passports did not look like Asians, but he did not elaborate. Airport CCTV footage showed they completed all security procedures, he said.
"We are looking at the possibility of a stolen passport syndicate," he said.
About two-thirds of the 227 passengers and 12 crew now presumed to have died aboard the plane were Chinese. The airline said other nationalities included 38 Malaysians, seven Indonesians, six Australians, five Indians, four French and three Americans."
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I’m so done with this planet
she saved two lives and all they care about is her nipple.
this is sexism, my friends.
This is just fucking ridiculous! I’m sure the last thing she gave a shit about was her nipple coming out while she was SAVING HER CHILD AND THEIR NANNY!
Gotta love he fact that the story is about the nip slip and not the rescue. The rescue is just an afterthought.
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Did you know that pregnant women have been fired for using the bathroom to vomit, needing to carry a water bottle on the job, or asking to sit on a stool instead of standing in place all day? While employers have to make allowances like these for other types of temporary disabilities, a number of bad court decisions have encouraged them to feel they can get away with firing or mistreating pregnant workers with impunity.
It’s disgraceful and unacceptable that at a time when unnecessary budget cuts are decimating food, medical, and educational supports for low-income families, pregnant women continue to be pushed out of their jobs just as they take on all the expenses of having a new baby.
This is unacceptable. Pregnant workers need more protection. With a child coming up they need employment more than ever. Please contact your rep.
'No you can't have paid maternity leave'
'What do you mean you have special needs when you're pregnant?'
Pro-lifers, look closely. People can and do lose their jobs for being pregnant.
Yes and that’s why we need to keep fighting issues like this (as they are feminist causes) and not punishing/killing the babies because of the world they are being born into. Can you imaging being told your mother tried to have someone kill you (before she even met you) because of a job? That’s not to say the above situation isn’t completely awful, painful, and unfair; I just take issue with the implication that abortion will solve the problem.
Yes I think a better goal would be to end discrimination against pregnant people in the workplace.
Any politicians who call themselves pro-life and vote against this need to be asked why “protecting unborn children” doesn’t apply here.
(via prolifeforall)Source: action.rhrealitycheck.org