Saturday, February 20, 2010

Terahertz Waves Tear Apart DNA

How Terahertz Waves Tear Apart DNA
A new model of the way the THz waves interact with DNA explains how the damage is done and why evidence has been so hard to gather

Great things are expected of terahertz waves, the radiation that fills the slot 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.

The way terahertz waves are absorbed and emitted can also be used to determine the chemical composition of a material. And even though they don't travel far inside the body, there is great hope that the waves can be used to spot tumours near the surface of the skin.

With all that potential, it's no wonder that research on terahertz waves has exploded in the last ten years or so.

But what of the health effects of terahertz waves? At first glance, it's easy to dismiss any notion that they can be damaging. Terahertz photons are not energetic enough to break chemical bonds or ionise atoms or molecules, the chief reasons why higher energy photons such as x-rays and UV rays are so bad for us. But could there be another mechanism at work?

The evidence that terahertz radiation damages biological systems is mixed. "Some studies reported significant genetic damage while others, although similar, showed none," say Boian Alexandrov at the Center for Nonlinear Studies at Los Alamos National Laboratory in New Mexico and a few buddies. Now these guys think they know why.

Alexandrov and co have created a model to investigate how THz fields interact with double-stranded DNA and what they've found is remarkable. They say that although the forces generated are tiny, resonant effects allow THz waves to unzip double-stranded DNA, creating bubbles in the double strand that could significantly interfere with processes such as gene expression and DNA replication. That's a jaw dropping conclusion.

And it also explains why the evidence has been so hard to garner. Ordinary resonant effects are not powerful enough to do do this kind of damage but nonlinear resonances can. These nonlinear instabilities are much less likely to form which explains why the character of THz genotoxic
effects are probabilistic rather than deterministic, say the team.

This should set the cat among the pigeons. Of course, terahertz waves are a natural part of environment, just like visible and infrared light. But a new generation of cameras are set to appear that not only record terahertz waves but also bombard us with them. And if our exposure is set to increase, the question that urgently needs answering is what level of terahertz exposure is safe.

Ref: DNA Breathing Dynamics in the Presence of a Terahertz Field

Wednesday, February 17, 2010

Peter Kent Says...


Steven Chase

Ottawa — Globe and Mail Update Published on Tuesday, Feb. 16, 2010 10:53PM EST Last updated on Wednesday, Feb. 17, 2010 7:52AM EST

Junior Foreign Affairs minister Peter Kent is suggesting Canada would rush to Israel's defence in a military confrontation, telling a Toronto publication that "an attack on Israel would be considered an attack on Canada."

But he later declined to say whether this means that Canada would automatically declare war on an aggressor attacking Israel.

In an interview published Feb. 12 in Shalom Life – discussing the threat from Iran – Mr. Kent said: "Prime Minister Harper has made it quite clear for some time now and has regularly stated that an attack on Israel would be considered an attack on Canada."

Mr. Kent's statement appears to be evidence the Harper government is shifting to an even stronger pro-Israel stance.

His wording – which goes beyond Mr. Harper's previous comments on Israel – evokes Article 5 of the NATO treaty which says "an armed attack against one or more [parties] in Europe or North America shall be considered an attack against them all."

In an interview with The Globe and Mail, Mr. Kent, Minister of State for Foreign Affairs of the Americas, dismissed the idea he was altering Canadian foreign policy, saying his comments paraphrased what Stephen Harper has said before.

Mr. Kent declined to say whether this means Canada is ready to join a war against a country that attacked Israel.

"You're putting words in my mouth; we don't have to be this absolute," he said.

At the same time, Mr. Kent sounded a warning note, saying that even though Israel and Canada don't have a military treaty – like the NATO pact – Ottawa is not bluffing.

"There is no military treaty but I think the Prime Minister's … commitment is quite clear: We don't pay lip service to our commitments to friends and allies."

He apologized for the "sometimes imprecision of diplomacy," but said Israel is clear on what Canada means.

"Israel is not in any doubt … as to the degree of Canada's commitment," Mr. Kent said. "And I would hope that any potential aggressor would consider that seriously."

Shimon Fogel, CEO of the Canada-Israel Committee, said it's hard to predict exactly what Canada's commitment would entail in the event of an attack on Israel by Iran.

But he lauded Canada's decision to stand in solidarity with Israel as a democracy. "It's an incredibly positive and assertive comment," he said. Mr. Fogel said it's also recognition an attack on Israel would have an incredibly destabilizing impact on the region. He said statements such as Mr. Kent's ultimately send a signal to Iran that Canada will stand together with Israel if it is attacked.

"We're not simply talking about a rhetorical statement," he said.

The Prime Minister's Office backed up Mr. Kent, saying his words mirror what Mr. Harper has said before, including a speech in May, 2008, in which he said: "Those who threaten Israel also threaten Canada, because, as the last world war showed, hate-fuelled bigotry against some is ultimately a threat to us all, and must be resisted wherever it may lurk."

Khaled Mouammar, national president of the Canadian Arab Federation, panned Mr. Kent’s comments, saying Canada is joining arms with a country alleged to have committed war crimes in Gaza strip during the 2008-09 conflict there.

"It is regrettable that our government has chosen to ally itself with the government of Israel which the United Nations fact finding mission, led by renowned Jewish South African judge Richard Goldstone, found guilty of committing war crimes and crimes against humanity in Gaza," Mr. Mouammar said in a statement.

The extremely controversial UN report by Mr. Goldstone in fact accused both Israel and Hamas of war crimes during the 2008-09 conflict.

Sunday, February 14, 2010

Shrimp Wars: Faroes, Greenland Shut Out of Canadian Ports

Canada to close ports to Faroes, Greenland vessels
Last Updated: Sunday, February 14, 201
CBC News

Canada is going to close its ports to vessels from the Faroe Islands and Greenland on Monday because of shrimp overfishing, federal Fisheries Minister Gail Shea said Sunday.

The Faroes and Greenland have refused to abide by quotas set by the North Atlantic Fisheries Organization (NAFO), which sets catch limits for each member.

"We have acted in good faith for several years to try to resolve this issue, to no avail," Shea said in a news release.

Canada originally closed its ports to vessels from the Faroes and Greenland in December 2004, but reopened them in March 2008 as a sign of good faith.

Now, however, the minister has followed up on a warning issued Jan. 26, when she said the ports would be closed unless the Faroes and Greenland withdrew an objection to the NAFO shrimp quota in NAFO area 3L, in the north Atlantic east of St. John's beyond Canada's 200-mile limit.

Denmark, which acts on behalf of the Faroes and Greenland in international matters, unilaterally set a 3L shrimp quota of 3,101 tonnes, almost 10 times greater than their NAFO quota of 334 tonnes.

"Their continued overfishing is unacceptable," Shea said on Jan. 26.

The minister said Sunday she would be willing to meet her counterparts from the Faroes and Greenland to resolve the issue "at their earliest convenience."

Both the Faroe Islands and Greenland are self-governing overseas administrative divisions of Denmark.

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