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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."
continuity of the state and its power structures is far more important than petty things like individual freedoms or human lives.
Resonant effects build up from very small amplitudes; the 'safe' level of exposure from a CW machine is none.
If they had two lanes that'd be fine and dandy. But refusing to be searched and requesting to be done by hand is making yourself a suspect. As soon as you ask that enjoy being treated like you tried to sneak a gun on board.
What is this ethics thing you are talking about and since when was it relevant to fight in a political arena ?
The Wise adapts himself to the world. The Fool adapts the world to himself. Therefore, all progress depends on the Fool.
>>>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
This is good science. It gives experimental research a direction to look in. If they find the same result it will validate this computer model, if they still can not the computer model needs to be thrown out or reworked. There will always be differences between theory and experiment, this is probably just one of those cases.
It may not matter though, with the number of people that can not differentiate between theory and reality this may stop terahertz scanning dead since people are dumb and panicky when it comes to crap like this. People still think WiFi or cell phones can give you cancer. Better yet, most people can't even tell you the difference between a tumor and cancer and use the terms interchangeably.
i thought all DNA was double stranded. Is there single or triple stranded DNA? If all DNA is double stranded, why mention strandedness at all?
i'm not trolling, i'm asking a question. Yesterday some jerks with more mod points than sense labeled me as a troll for asking questions.
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Actually, it's a theoretical explanation for some difficult experimental results. The issue was that some studies suggested that THz radiation would be harmful at any frequency/power range, while others pegged it as only being significant at particular resonant amplitudes or frequencies. It transpires that in the presence of thermal perturbations, you do indeed get some non-specific disruption of the base pairing, which would only be an issue if you had a long enough exposure to actually get a significant thermal perturbation and thus cause a very significant disruption. However there is also a resonant mechanism, at a particular frequency with a critical minimum amplitude, that can immediately cause a significant disruption, without the need to wait for a particularly big thermal perturbation. That's my reading, anyway.
No kidding!!! What do you say at this point?
Might not be for bomb reasons, could be smuggling of drugs, money or other materials. If I was running a security service, I'd find it unusual that someone buys a one-way ticket one hour before a flight. At least enough to frisk them for goodies.
Already, a friend of mine that's a cell phone addict (and has been since they were 'perfected') has had numerous benign growths removed from her face.
[citation needed].
You need to understand the difference between ionizing radiation and non-ionizing radiation. Don't try to draw a correlation between benign growths and cellphone use. Your local AM radio station, an old microwave that isn't properly insulated, your television with rabbit ears, your cordless phone, your 802.11x access point in your house, and many others are also hitting you with non-ionizing radiation.
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.
>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!
Airports use metal detectors for humans, not xrays. The new millimeter wave machines arent xrays. As far as safety, have is been demonstrated that these machines damage organisms in regular usage? It seems to me that a lot of this is reactionary nonsense like "I'm allergic to wifi!!" nonsense.I am concered about safety, but jumping on the naturalist/homeopathy/conspiracy theory bandwagon doesnt do us any good.
Not to mention just flying on a plane gives you a nice dose of cosmic rays, sans superpowers.
>not the invasion of their privacy!
Yes, lets give up on airport security. That will end well.
>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.
Awesome, now I can watch someone try to organize a class action lawsuit against Apple because they claim that the iPhone gave them herpes.
*grabs popcorn*
As long as they don't subject all airport service personnel, like baggage handlers, to the same level of screening, then these games will provide no significant improvement in security.
When information is power, privacy is freedom.
I know this is slashdot, but did you read anything before replying? The article in discussion (at the top of the page fyi) discusses the discovery that millimeter wave radio waves appear to be resonant with DNA, resulting in significant DNA damage. Yes the new millimeter wave machines are not Xrays. But this is new research that shows that the effects may be greater than anticipated. It certainly bears looking into to determine if there is a problem.
The parent poster was drawing a similarity in the use to that of the use of XRays for fitting shoes. He certainly wasn't talking about giving up on airport security. The metal detectors work quite well. I haven't seen much evidence that spending a lot of money to allow some barney fife to look at my privates is going to significantly increase the security of flying. And to those who modded you insightful, get a clue!
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Makes sense to me. If I was going to hi-jack a plane I wouldn't dress up like a stereotypical terrorist. Its going to be the seemingly innocent ones who are going to sneak things on.
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And so you drive by several antenna towers, each pumping out several megawatts at freqs ranging from the 540khz range through FM around 100mhz to TV starting under 100mhz to say 600mhz+. You add in cells starting in at 450mhz and various VHF/UHF transmitters-- yes, at a lower power.
But as you travel by the non-microwave towers, and their 20-30megawatts comes into close proximity to you, you might recall the days of St Elmo's fire, when there was enough EMF being broadcast to make fences literally glow and dance with little electrons.
Now, you carry a cell/mobile on your body, somewhere. In your ear might be a microwatt bluetooth device at 2.4ghz, and your laptop is using similar or 5ghz spectra at several milliwatts.
The aggregate amount of EMF exposure is pretty high compared to say, 1900 when there was effectively on the amount generated by lightning. Are DNA immune to electrons and various state charges? If so, at what freqs and with what kinds of modulation?
Lack of research! Yes-- now you get the point.
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