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USA’s outdated ineffective nuclear weapons strategy

Time to fix our seriously misaligned nuclear strategy, THE HILL, By Brig. Gen. Stephen A. Cheney, USMC (Ret.), and Matthew Wallin – 05/31/13  In anticipation of the G8 summit next month, we can expect serious discussion to be held about how to address today’s nuclear threats, including proliferation, the risks posed by the Iranian nuclear program and North Korean provocations.

As we have seen over the past 12 years, should a military response be deemed necessary to meet these threats, the U.S. has demonstrated itself to be the most effective practitioner of symmetric warfare the world has ever seen — but addressing asymmetric challenges has proven significantly more difficult.

Our experiences have shown that the biggest threats to our warriors have not been other armies, but IEDs; the biggest threats to our ships have not been big navies, but small boats and missiles. And today, the biggest threats to our nuclear security are asymmetric as well.

Despite this, and more than two decades after the end of the Cold War, we still maintain a vastly oversized nuclear arsenal designed to destroy a country 185 times the size of North Korea. This strategic misalignment leaves an enormous gap in our ability to counter modern nuclear threats. The more than 1,500 deployed nuclear weapons currently in our arsenal may have been historically effective in deterring a nuclear exchange with the Soviet Union, but this arsenal has done nothing to deter the ongoing proliferation of such weapons.

While we continue to have political disagreements with Russia, we both agree that maintaining massive nuclear arsenals no longer holds the strategic utility it did decades ago. The situation is ripe for change.

We should therefore seize this prime opportunity and realign our nuclear strategy to counter adversaries that pose real nuclear threats. Thus far we are making the grave mistake of not adapting, for example, this year, the administration’s budget request oddly increases funding for nuclear weapons by 17 percent — a choice that does nothing to neutralize the actual capabilities of our adversaries.

So what should a properly aligned nuclear strategy look like?……..

And finally, we must continue to work with Russia and other countries in order to reduce the enormous size and expense of our nuclear arsenals, thereby allowing us to redistribute those funds to the tools and programs designed to address real and potential threats. It certainly makes more sense than throwing money away to counter a security challenge that no longer exists.: http://thehill.com/blogs/congress-blog/homeland-security/302741-time-to-fix-our-seriously-misaligned-nuclear-strategy#ixzz2Uzswk25w

June 1, 2013 Posted by | USA, weapons and war | Leave a comment

More radiation exposure when contrast medium is used with CT scans

Contrast use spikes CT radiation dose, By Eric Barnes, AuntMinnie.com staff writer, May 30, 2013 –– The use of contrast media during CT scans significantly increases how much radiation patients absorb in amounts that vary by organ, researchers report in the June edition of the American Journal of Roentgenology. Radiologists should account for the expected dose increases when setting scanner protocols, they said.

Radiation dose increased for every organ scanned at CT, particularly in the most vascularized tissues, wrote researchers from the University of Messina in Italy. Average doses rose by one-fifth for the liver, one-third for the spleen and pancreas, and almost three-fourths for the kidneys.

“The results are in agreement with our previous data, confirming an increase in organ radiation dose in contrast-enhanced CT compared with unenhanced CT,” wrote Dr. Ernesto Amato and colleagues (AJR, June 2013, Vol. 200:6, pp. 1288-1293)……

Investigators have also found an increase in the frequency of cellular abnormalities in patients who underwent contrast-enhanced radiographic examinations. But the actual increase in dose for any given scan — which depends on iodine uptake; the shape, volume, and position of the organ; and the emitted x-ray energy spectrum — remains unknown, the authors wrote…….

Confirming dose increases

The results were in line with the group’s previous phantom study, and they confirmed significant radiation dose increases in contrast-enhanced CT versus unenhanced CT, Amato and colleagues wrote. The data showed average dose increases of 19% for the liver, 71% for the kidneys, 33% for the spleen and pancreas, and 41% for the thyroid.

“The kidneys showed the maximum among the average dose [increases] (71%, resulting from an attenuation increment of 139 HU),” the authors wrote.”High renal enhancement is, in fact, due to both their high vascularization because they receive 20% to 25% of the cardiac output and the passage of iodine within the renal tubules. In particular, the level of contrast medium within renal tubules can be up to 50 to 100 times higher than that in the blood because of the mechanisms of tubular concentration and secretion.”

Thyroid tissue showed the second highest dose increase (41%) after contrast injection, based on an HU increase of 87%. Also, the dose increases in the thyroid depended on tissue density on unenhanced CT, the group noted. Denser thyroids showed a lower increase in attenuation and, consequently, lower increases in dose.

Because the liver and spleen are richly vascularized, Hounsfield units increased with contrast by 49 HU and 71 HU, respectively, and average dose increased by 19% and 33%……. http://www.auntminnie.com/index.aspx?sec=ser&sub=def&pag=dis&ItemID=103565

June 1, 2013 Posted by | radiation, Reference, USA | Leave a comment

Iran converting much enriched uranium to non weapons usable form

Uranium conversion may help ease bomb fears, Japan Times, 1 June 13 VIENNA – An important recent development in Iran’s nuclear program, if it continues, might help to ease international fears that Tehran wants the bomb, but serious questions still remain, analysts and diplomats said.

This potentially positive step, as highlighted in recent quarterly reports by the International Atomic Energy Agency, concerns uranium enriched by Iran to a fissile purity of 20 percent.

This material is of major international concern because if further purified to 90 percent — a process well within Iran’s technical capabilities — it would be suitable for a bomb.

According to the IAEA’s most recent report, Iran has produced 324 kg of uranium enriched to 20 percent, well above the about 240 kg thought to be needed for one nuclear device — which is reportedly also Israel’s “red line”.

But more than 40 percent of this has been converted into another form, triuranium octoxide, which experts say is tricky to convert back to the original uranium hexafluoride.

Iran says that it is converting this uranium in order to provide fuel for a reactor in Tehran, and four others that outgoing President Mahmoud Ahmadinejad last February ordered constructed, for nuclear medicines.

Tehran also calls it a “confidence-building” measure in so-far fruitless talks with six world powers on hold until after the presidential election on June 14…… http://www.japantimes.co.jp/news/2013/06/01/world/uranium-conversion-may-help-ease-bomb-fears/#.UapgdNJwo6I

 

June 1, 2013 Posted by | Iran, Uranium, weapons and war | Leave a comment

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