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Sonja Bäumel lives and works in Vienna and Amsterdam. Her artefacts mediate between art and science, fashion and science, design and science, between clothes and body, between fiction and facts. Her works evolve from permanent confrontation with scientific data and facts, which she often generates herself in experiments and in research labs.

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This door handle kills germs

UV light, powered by the door’s movement, triggers the microbe-killing power of the handle’s coating

BY

SID PERKINS

PITTSBURGH, Pa. — Diseases spread in many ways. An infected person can cough or sneeze on someone nearby. Or, they can transfer germs through a handshake. But sometimes we pick up germs indirectly. A sick person might leave behind bacteria or viruses when they touch a doorknob, handrail, shopping cart handle or countertop. Anyone else who touches that surface may pick up the microbes. But what if those surfaces could disinfect themselves?

Two teens from Hong Kong asked themselves the same question. Now they’ve developed a door handle that can knock out germs on contact.

The concept is simple. Every time the door is opened, the movement creates power that triggers a germ-killing reaction on the handle. In lab tests, their system killed about 99.8 percent of the germs that they spread onto lab dishes coated with their material.

Research by others has shown that door handles in public areas often host lots of bacteria and viruses, notes 17-year-old Sum Ming (“Simon”) Wong. The tenth grader attends Church of Christ in China Tam Lee Lai Fun Memorial Secondary School in Tuen Mun, China. He and schoolmate Kin Pong (“Michael”) Li, 18, wanted to design a coating for door handles that would be hostile to germs.

After doing some research, they learned that a mineral called titanium dioxide is known to kill bacteria. It’s already used for other purposes in many products, from paints to sunscreens to edible puddings. To make their coating, the teens ground the mineral into a very fine powder.

Titanium dioxide kills bacteria best when lit by ultraviolet (UV) light, says Simon. UV wavelengths are among those in sunlight. But indoor handles and any used at night would have little natural exposure to UV light. So the teens are lighting their door handle from within. Now, every part of the coated handle will see UV light.

To make sure the interior light reaches the coated surface, the teens fashioned their door handle from a long cylinder of clear glass. Each end fits into a bracket. Inside one of the brackets is a strong light-emitting diode (LED). It emits UV light. (Transmitting the light from one end of the handle to the other is similar to the transmission of light through a fiber-optic cable. In this case, though, the glass handle is fat rather than super-thin.)

And here’s the nifty part: The power that makes the UV light shine comes from opening and closing the door. Simon and Michael designed a small gearbox that attaches to the door. Equipment inside the box converts the motion of those gears into electrical power. That power is then carried by wire to the light-emitting diode inside the door handle.

The teens presented details of their research here at the Intel International Science and Engineering Fair. This event was created by the Society for Science and the Public (which also publishes Science News for Students). The annual competition is sponsored by Intel. This year, it brought 1,702 finalists to Pittsburgh in mid-May from more than 70 countries.

The door handle system, Michael and Simon say, might cost no more than about $13 to build.

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anonymous asked:

why does your breath smell bad when you wake up?

Warning: this is gross.

It’s because colonies of bacteria have been growing in your mouth all night.

Bacteria really love the inside of the human body, and your mouth is no exception. Saliva normally keeps things under control by sweeping away bacteria and the food particles they eat. But at night, when you aren’t producing as much saliva, your mouth becomes a prime breeding ground. As the colonies grow, more and more bacteria feast on food particles and dead cells, producing a bunch of different odor-causing compounds as waste products – like one called cadaverine. 

So when you say your mouth smells like a corpse in the morning… that’s not really an exaggeration.

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Florida beaches are currently suffering from the presence of Vibrio vulnificus bacterium, a rare flesh-eating bacteria, that has caused seven deaths this season, and infected at least 32 in the past year.

“People get Vibrio by swimming, wading and playing in salt or brackish waters with open wounds or scratches,” said Dr. Carina Blackmore, the deputy state epidemiologist in Florida.

Time to stay away from the beach forever… 

Scientists discover a bacterium that “breathes” uranium and renders it immobile

A strain of bacteria that “breathes” uranium may hold the key to cleaning up polluted groundwater at sites where uranium ore was processed to make nuclear weapons.

A team of Rutgers University scientists and collaborators discovered the bacteria in soil at an old uranium ore mill in Rifle, Colorado, almost 200 miles west of Denver.  The site is one of nine such mills in Colorado used during the heyday of nuclear weapons production.

The research is part of a U.S. Department of Energy program to see if microorganisms can lock up uranium that leached into the soil years ago and now makes well water in the area unsafe to drink.

The team’s discovery, published in the April 2015 issue of Public Library of Science (PLoS), is the first known instance where scientists have found a bacterium from a common class known as betaproteobacteria that breathes uranium. This bacterium can breathe either oxygen or uranium to drive the chemical reactions that provide life-giving energy.

“After the newly discovered bacteria interact with uranium compounds in water, the uranium becomes immobile,” said Lee Kerkhof, a professor of marine and coastal sciences in the School of Environmental and Biological Sciences. “It is no longer dissolved in the groundwater and therefore can’t contaminate drinking water brought to the surface.”

Sign at shuttered uranium mill in Rifle, Colorado, warns onlookers of hazards that remain from Cold War era nuclear weapons production.. Credit: Bill Gillette, U.S. National Archives and Records Administration      

Antidepressant Microbes In Soil: How Dirt Makes You Happy

Lack of serotonin has been linked to depression, anxiety, obsessive compulsive disorder and bipolar problems. The bacterium appears to be a natural antidepressant in soil and has no adverse health effects. These antidepressant microbes in soil may be as easy to use as just playing in the dirt.

Most avid gardeners will tell you that their landscape is their “happy place” and the actual physical act of gardening is a stress reducer and mood lifter. The fact that there is some science behind it adds additional credibility to these garden addicts’ claims. The presence of a soil bacteria antidepressant is not a surprise to many of us who have experienced the phenomenon ourselves. Backing it up with science is fascinating, but not shocking, to the happy gardener.

Mycrobacterium antidepressant microbes in soil are also being investigated for improving cognitive function, Crohn’s disease and even rheumatoid arthritis.

 Deinococcus radiodurans - the bacterial nuclear survivor

So on the topic of extremophiles after some of you guys really wanted to hear about crazier organisms than the tardigrade. D. radiodurans is one of my favourites because it can survive an insane number of extreme climates and no-one is quite sure the exact reason as to why such an organism evolved leading some scientists to believe it may have colonised Earth through panspermia (although its genetic make-up is to similar to that of other organisms for this to be a viable reason). It was identified in 1956 when scientists were experimenting with gamma radiation as a means of sterilising canned foods. a can of food exposed to gamma radiation thought to kill all forms of life spoiled due to this microbe.

D. radiodurans has a number of nifty little adaptations that help it withstand up to 5000Gy of ionising radiation with little loss in viability. For one, you can see in the image above that the spherical cells form a tetrad. Each cell within the tetrad also contains 4 identical circular copies of the genome. So each tetrad has 16 identical copies of the same genome. What this allows for is homologous racombination, to allow repair of broken fragments of DNA. The cells in the tetrad frequently take up fragments on DNA from neighbouring cells to improve repair. 

So why has such an ability evolved? It is unlikely that such conditions have ever existed on Earth as few other organisms can survive anywhere near the same amount of radiation, but the ability to repair its DNA so well is most likely a lucky evolutionary accident that has stemmed from it resistance to dessication in incredibly dry environments as the mechanisms with dealing with both are highly similar.

This bacteria is also able to withstand cold and acidic environments as well as vacuums. Current applications for the bacteria include using it in bioremediation to clear up radioactive, polluted sites where solvents and other toxic compounds contaminate the area. 

Further reading: Genomesnetwork

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World’s first photosynthetic living matter-infused 3D-printed wearable

Speaking at the 2015 TED conference in Vancouver, Canada, MIT professor Neri Oxman has displayed what is claimed to be the world’s first 3D-printed photosynthetic wearable prototype embedded with living matter. Dubbed “Mushtari,” the wearable is constructed from 58 meters (190 ft) of 3D-printed tubes coiled into a mass that emulates the construction of the human gastrointestinal tract. Filled with living bacteria designed to fluoresce and produce sugars or bio-fuel when exposed to light, Mushtari is a vision of a possible future where symbiotic human/microorganism relationships may help us explore other worlds in space.