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How Terahertz Waves Tear Apart DNA
KentuckyFC writes "Great things are expected of terahertz waves, the radiation in the electromagnetic spectrum between microwaves and the infrared. Terahertz waves pass through non-conducting materials such as clothes, paper, wood and brick and so cameras sensitive to them can peer inside envelopes, into living rooms and 'frisk' people at distance. That's not to mention the great potential they have in medical imaging. Because terahertz photons are not energetic enough to break chemical bonds or ionize electrons, it's easy to dismiss fears over their health effects. And yet the evidence is mixed: some studies have reported significant genetic damage while others, although similar, have reported none. Now a team led by Los Alamos National Labs thinks it knows why. They say that although the forces that terahertz waves exert on double-stranded DNA are tiny, in certain circumstances resonant effects can unzip the DNA strands, tearing them apart. This creates bubbles in the strands that can significantly interfere with processes such as gene expression and DNA replication. With terahertz scanners already appearing in airports and hospitals, the question that now urgently needs answering is what level of exposure is safe."
Who cares if we turn into an entire country of genetically deformed freaks, at least we'll be a country of SAFE and FREE genetically deformed freaks, right? Just as envisioned by our Founding Fathers. God Bless America.
Although store clerks were frequently exposed to the radiation from the machines, the radiation was more dangerous to children who placed their feet directly into the radiation. The exposure rate is thought to have been approximately 0.005 Gy to 0.058 Gy per second. If children tried on several pairs of shoes per visit it was posited that they could be exposed to as much as 0.1 Gy to 1.16 Gy. In fact, experiments indicated that radiation could exceed 1 microGy per hour as far as 10 feet away from the machine.
This device should be a warning (and I think it has been if you look at how cautious people are of new technologies like cell phones). Hopefully my sperm aren't being fried when I walk through a scanner in an airport--at least the parents of the 30s were using X-rays for their convenience and not the invasion of their privacy!
My work here is dung.
continuity of the state and its power structures is far more important than petty things like individual freedoms or human lives.
So if there's a hysterical OMGCancer panic amongst the scientific illiterate, is it ethical to take advantage of that to protect ourselves against the privacy abuses of these things at train stations and airports and on the street?
Aide-toi, le Ciel t'aidera - Jeanne D'Arc.
If you follow the link provided about the airport scanners you find that they are passive devices meaning they don't emit terahertz waves they only recieve the waves coming off of everything around us.
There are some devices out there that using terahertz radiation to inspect packages much like x-ray today.
The times I've encountered the terahertz scanners at airports, they've always been optional (although they don't make it clear to you that it is). If directed to one, I've always simply asked if I must use it or if I had a choice of a "normal" metal detector. EVERY time they've allowed me to choose (and I travel a LOT). Most times they take a note of it or ask me to sign a sheet to indicate my declination - I assume so they can figure out if people object or not.
Asking the quesiton never hurts. It also sends the message that this intrusion isn't accepted by the public. Don't surrender to these things willingly.
I used to have a sig, but I set it free and it never came back.
You would deprive us of hundreds, if not thousands, of leaked nude photos of famous celebs just to save a little DNA?!?!? Are you insane, man????
SJW: Someone who has run out of real oppression, and has to fake it.
If you read the story this conjecture is the results of a computer model ...NOT real measurements of actual damage to DNA - since no previous actual experiments have turned up any damage then I'd say the model is not quite right - at any rate its all theoretical and not proven with experiment
>>>People don't realize it, but our bodies birth cancerous cells constantly. We usually kill them off, though.
Yes but irritants (like tobacco smoke) create MORE cancerous cells, and therefore increase the odds you'll die of cancer. The solution is to avoid those things that encourage cancerous growth.
"I disapprove of what you say, but I will defend to the death your right to say it." - historian Evelyn Beatrice Hall
The summary mentions that the terahertz waves "tear apart" strands of DNA. For those who might not remember their undergraduate biology, DNA strands are held together by hydrogen bonds - not covalent bonds. So the total amount of force to "tear apart" two strands is not as great as you might imagine. For that matter, strands have to be "torn apart" in order to be replicated for cell division.
Damn_registrars has no butt-hole. Damn_registrars has no use for a butt-hole.
Build and sell a four-in-one! You can be your first customer!
That's odd. I get just one result, from someone named "visualight" on Slashdot!
Actually, when I decline, they've always walked me to the front of the line for the other detectors. It's saved me time in the end, strangely enough.
A few other times, when it was my turn, I simply walked to the standard detector myself, and had no issues.
(they have two normal lanes and one terahertz scanner lane at my departure airport, but I've run into them in many other places recently too)
I used to have a sig, but I set it free and it never came back.
Single-stranded DNA has its information-encoding side exposed and flops around kind of pathetically. Double-stranded DNA sticks the two information-encoding sides together so that they're hidden and inactive, and helps you wind up and store the DNA. However the double strand can "unzip" along a small part of its length to expose two single strands which can go to work.
You can get triple-stranded DNA, but it's not traditionally been thought of as important. Normally the groove for the third strand would be occupied by proteins involved in the function and maintainence of the DNA instead. However it now seems that forming a triple strand in some regions might be important in DNA's control mechanisms too.
No kidding!!! What do you say at this point?
But what if Terahertz waves can also be used to kill a cancerous tumor? Think about this ... take to sources of focused EM energy beams, neither in the Terahertz range, and aim both energy beams at a cancerous tumor. When the two energy beams coincide at the tumor, through constructive interference, localized Terahertz waves are generated that disrupt the DNA of the cancer cells to the extent that those cells can no longer replicate. Since the energy is localized, damage to the surrounding body tissue is minimal and can be repaired by the body in a short time. As a result though, the cancer is gone.
Wait a moment, folk! We are talking about temporary separation of already uncoiled DNA (meaning, that it's probably under the process of being expressed, anyway) under very specific conditions as predicted by a computer model.
This is not even an empirical observation: we don't know that any of this happens in a cell free in vitro system and how significant the effect is (if any), we don't know if it happens in a cell culture in vitro system and how significant the effect is (if any) and we certainly don't know that anything like this happens in vivo.
Even assuming that you can create these precise conditions by an airport scanner (which seems rather doubtful), you certainly would not, in any way, be facilitating mutation in any appreciable sense*. All that you would be doing, theoretically, is to subtly alter patterns of gene expression for the few seconds it would take to walk through the scanner (basically, a very subtle regulatory effect). While you certainly can facilitate the development of cancer through such a mechanism (in fact, I'd argue that dysregulation of gene expression** at some points is simply required for carcinogenesis --yes, it can be caused by mutating proteins but these mutated proteins are almost invariably going to have direct or indirect regulatory functions***), such a dysregulation of gene expression would have be the prolonged, normal state of affairs of a cell for a cancer to actually happen. For this to be happening (in a worse case scenario) for as much as a few mere seconds can hardly even be called a dysregulation in any meaningful sense and much, much less have any effect, whatsoever, on carcinogenesis.
If, on the other hand, some government agency is monitoring you 24/7 with these scanners, then you might have reason to worry****.
* I would speculate that there's an infinitesimal chance that DNA might be more susceptible to mutations from not being as protected as it would be when paired but you have to realize that active regions of DNA get unzipped like this all the time so this effect, if it might be real, would be a drop in the bucket and utterly swamped by the background.
** For purposes of this discussion, what I mean by dysregulation of gene expression is the production of various protein products at inappropriate times or in the wrong amounts (either too much or too little of a protein).
*** Whether the function is to induce cell division or stop cell division, or to induce cell death (apoptosis) or to evade cell death (and whether it is a direct or indirect effect on the preceding --such as mechanisms sensing DNA damage, loss of contact inhibition, etc.). While other factors which may not always be strictly regulatory do exist such as invasiveness, angiogenesis, telomerase function, etc (which often will also be regulatory by involving over or under expression); these factors need to happen together with a regulatory dysfunction for an actual cancer to happen because, basically, cancer happens when a lot of different sorts of things get screwed up at the same time.
**** About adjusting your medication dose, that is.
>Needless to say, everyone in line was a bit pissed that the TSA was giving extra screening to the old lady when they just waved the Arab guys through without a second glance.
Err, racial and religious profiling has serious drawbacks. Random testing along with metal detectors, milimeter scan, etc is a better way. Not to mention terrorists arent stupid. Theyre not going to dress up in full garb. The 9/11 hijackers wore street clothes and business casual clothes.
Terrorists and drug smugglers also prey upon the weak and stupid. I can remember how many times Ive been asked to "hold my bag please, it is a package for my son" in line to get on a plane or a train.
>"What the fuck are you morons searching her for? The towelheads are the ones flying shit into buildings!"
Stay classy.
>Maybe scanned him a few extra times to make sure his DNA was totally fucked up.
With what exactly? The passive metal detector and passive millimeter wave device? Perhaps it would behoove us all in air travel if didnt point at funny looking people and scream "terrorist" like the moron in your story.
Ha! No, they don't. In theory you could do this, but not quickly. The data volume alone should make it obvious they aren't doing this. The model you describe would be terabytes in size. On top of that, creating the model would require a huge amount of supercomputer time. There's just no way they are doing this quickly in a line at an airport. I *wish* it was that easy, since my job involves radar imaging.