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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."

2 of 279 comments (clear)

  1. Re:Ethical use of panic... by BadAnalogyGuy · · Score: 0, Troll

    The concept of a clear box as some sort of booth for performing searches is so far removed from my concept of what America ought to be that I'm terribly saddened and honestly angered that this country has gone so far towards fascism and jack-booted thuggery in so little time. While you may not feel much shame, in general people would usually prefer to be taken to an area that maintains some semblance of privacy in the odd event that such a search is necessary. That we are searching people at all with this much effort is a travesty.

    As for getting an attractive person to pat you down, I can only say that I hope you are gay or bisexual because the guard who pats you down is required to be the same gender as you. Of course you already have piercings, so it may go without saying.

  2. Yeah... So here's how I think it will REALLY go... by Fantastic+Lad · · Score: 0, Troll

    After some initial buzz, this theory will be found highly debatable, the DNA damaged in some tests will be discovered to have been the result of poor testing, the damage will be considered within the normal range of every day life beneath a solar object like our Sun, and generally the whole issue will be relegated to the FUD desk and there forgotten except by the reactionary fringe which seems incapable of doing its homework.

    All while the real issue remains tidily ignored. And why? Because wave forms are the key to everything, so the black hats are going to do their utmost to retain control over the control, as it were.

    (Side note; I recently worked out how those giant megalithic blocks of stone might have been moved using, as is claimed, simply sound. It's so blindingly obvious that I actually smacked my forehead when I realized the basic principal behind it. --You know how when your cell phone is set to 'vibrate' rather than ring, and it sort of slides across the table? Same thing. Just broadcast a sound on the same resonant frequency as the big object you want to move, set it vibrating and then just push. Big blocks of stone remain heavy, but I imagine once you remove friction from the equation, building one of the thousands of megaliths dotting the planet becomes a somewhat more reasonable task.)

    Anyway, the real issue, in case anybody cares, has little to do with the high frequency carrier signal itself in a cell phone handset, (other than that it makes the whole game possible), but rather the modulated frequencies in the 10Hz to around 500Hz range where cells start doing peculiar things when exposed. --Odd things like opening and closing cell-wall permeability to particles in the blood, (this is of particular moment with regard to the Blood Brain Barrier). Keeping in mind that this occurs well below the power levels at which ionization is observed.

    But so what? Cell phones move data in the kilobytes per second range, well above the 10 - 500 Hz where cells start doing the funky chicken when excited. Thing is, and here's the rub, with every model of cell phone right from their introduction onto the market, the technology has found some fundamental excuse for broadcasting modulated pulses within that exact range. For example, GSM phones use a system called, Time Division Multiple Access or TDMA for short.

    It is described thusly. . .

    To increase the number of users that can communicate with a base station at the same time, a technique called Time Division Multiple Access (TDMA) is employed that allows each channel to be used by eight phones. This is achieved by compressing each 4.6 ms chunk of information to be transmitted into a burst or pulse 0.58 ms long (1 ms or millisecond is a thousandth of a second). So the phones and base stations transmit for 0.58 ms, every 4.6 ms, which results in a 217 Hz pulse modulation* or variation in their output (217 Hz = 1/4.6 ms). For technical reasons, there is, in fact, additional data compression which leads to the phones and base stations transmitting 25 pulses but omitting every 26th , and so on. This produces further pulse modulation of the power output at the lower frequency of 8.34 Hz (= 217 Hz/26).

    Page 31 section 4.13 - Independent Expert Group on Mobile Phones

    This puts the common GSM cell phone directly in the 10 - 500 Hz range with several regular signals which nerve cells, and brain cells specifically respond to. Each of the other cell phone systems finds a similar excuse to pulse in this range.

    And, I suspect, the same will be true of the newer systems, but as per usual, this will not be explored in favor of alarmist and for the most part, (as far as I have been able to determine after reading this stuff for years), misleading stories about cancer. --While it is probably not a good idea for one's blood brain barrier to open up when toxins are coursing through the blood, I