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Bacteria Used To Fix Cracked Concrete
An anonymous reader writes "Researchers at the UK's University of Newcastle have created a new type of bacteria that generates glue to hold together cracks in concrete structures — that means everything from concrete sidewalks to buildings that have been damaged by earthquakes. When the cells have been germinated, they burrow deep into the concrete until they reach the bottom. At this point, the concrete repair process is activated, and the cells split into three types that produce calcium carbonate crystals, act as reinforcing fibers, and produce glue which acts as a binding agent to fill concrete gaps."
RTFA, it's not very long and explains just that fact you need; it does know when to stop.
This is the NSA, we're gonna geet U h@x0r5! Also, what is a h@x0r5?
You do realize that most waste products that can be used as you mentioned contain toxins themselves? Bottom ash and fly ash from coal plants is comparable to nuclear waste.
Supporter of the +1 Over Dramatic mod option. In memory of apk.
An older article with considerably more detail. Not sure if it's the same bacteria.
http://www.newscientist.com/article/dn19386-for-selfhealing-concrete-just-ad
What's the acidity of your lungs? Oh, I see. You didn't read the article. Carry on, then.
The problem, with bullet wound is... they are not always clean, you can have some clothes debris, or other dirt. Closing the wound is easy (well, relatively speaking) but cleaning it well enough is another thing.
Several hundred years? Try several thousand.
This engineered bacterium system was entered into the International Genetically Engineered Machine competition, so there's a lot more information about this project at the team's project page. In particular, there's a more thorough description of the kill switch the team engineered to prevent the spread of this bacterium beyond the target environment, the underlying mechanism being that sucrose must be available in the environment to prevent the bacterium from producing a toxin which kills itself.
"FDA staff reviewers expressed concern about the number of patients who were left out of the study because they died."
So basically, it had nothing at all do with the topic hand and your comparison "I'll just have bacteria in my yogurt for now" was completely meaningless since no one has suggested building new things with it since that wouldn't work anyway.
The main problem with a bullet wound is that it used to be a normal functioning part of the body and not a bullet wound...
Also, the concrete repair activity is produced by upregulation of genes natural to Bacillus subtilis, not by anything transgenic. The upregulation of these genes presents an energy cost to the engineered bacterium while providing no benefit- if these bacteria mutate, it is more likely to be towards the wild phenotype. In addition, the team responsible has added a kill switch which tells the bacteria to commit suicide if sucrose is not present.
"FDA staff reviewers expressed concern about the number of patients who were left out of the study because they died."
Right, and battery acid is really good at curing the common cold.
I dunno where you're getting this info, but no, bullets certainly do not "sterilize" anything. One of the leading causes of death historically has been infection. We're better at dealing with it today, but infections still occur on a regular basis:
"A gunshot is never sutured closed as the infection rate is very high. Bullets drag clothing into the wound and along the bullet track. Since clothing is of course not sterile, the wound is prone to infection if closed. Open wounds almost never get infected."
http://www.tacticalmedicalpacks.com/files/Combat_Tactics_Trauma_article.pdf
"We have presented a series of 120 consecutive operative cases of penetrating wounds of the abdomen-72 gunshot wounds and 48 stab wounds. The majority of patients were in the 18 to 40 age group. The infection rate was 22% for gunshot wounds and 4.8% for knife wounds."
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2609419/pdf/jnma00480-0069.pdf
If you've ever tried to pump glue into a crack in concrete, you'll quickly figure that out. It's somewhere between messy and inadequate as a repair method, and certainly doesn't get into the smaller cracks, let alone the microcracks. The idea here is to have the glue self-extend, filling the air pockets and microcracks that no glue with sufficient surface tension to stick could ever manage.
However I think where this will become a more useful technique is for fixing the kinds of surface cracks that ail structures exposed to repeated wet/freeze/thaw cycles -- the typical winter climate for the east slope of the Rocky Mountains. Mount Rushmore would seem to be a good candidate, since seasonal surface cracking is what's causing damage.
Concrete roads that suffer similar winter freeze/thaw damage could also benefit -- instead of trying to patch the road one crack at a time (usually an exercise in futility, culminating in yawning potholes), or having to dig up and replace the concrete (an extremely expensive job), just wash it with a slurry of this bacteria. That could even eliminate most of the seasonal damage, by filling the microcracks that are where freeze damage starts.
Imagine if your state and local highway departments could reduce their budgets by simply needing to do less repair on concrete-based roads. Even if you don't believe in reducing taxes when need is reduced, it would free up that budget to use elsewhere.
~REZ~ #43301. Who'd fake being me anyway?