MY NOTE: LONGTIME MESSAGE BOARD POSTER TUGBOAT, POSTED A STORY OUT OF THE NY TIMES REGARDING, THE OBAMA ADMINISTRATION BELIEF THAT AL QAEDA IS ATTEMPTING TO DEVISE "TOXIN" BOMBS, MADE FROM RICIN. (PLEASE READ THE COMMENTS, AND THE IMPORTANT DISCLAIMER AT THE BOTTOM OF THIS PAGE)
http://www.msnbc.msn.com/id/44128981/ns/world_news-the_new_york_times#.TkY06RzyDW8
Tug presented the very interesting hypothesis, that this threat, which has been known to the current administration for more than a year, is the reason for the huge "rush", by the private "arm" of the CIA, (which is known as IQT), to use funding supplied by the Transportation Security Administration, to contract with Advanced Photonix, (API), to develop a hand-held, low-cost, terahertz device which could be used in settings, and situations world-wide to detect, and defeat terrorist plans such as the one reported by the NY Times story.
I've talked about the anomaly detection device several times on this blog, with the first post reporting the original news release about this exciting development.
http://terahertztechnology.blogspot.com/2010/11/advanced-photonix-to-engineer-low-cost.html
I've written about the possible use of this revolutionary device to detect a wide range of threats such as counterfeit drugs. http://terahertztechnology.blogspot.com/2011/03/terahertz-inspection-provides-answers.html, and for Airport security, http://www.blogger.com/post-edit.g?blogID=124073320791841682&postID=4516394402794900153.
Those readers who stumble across this blog, may not be aware that THz, has the power of spectroscopy, which can detect the chemical composition of substances scanned. This would mean that such a device could detect traces of dangerous or explosive chemicals on a person, or in a package or baggage. Envision such devices being placed as a routine matter, in every public building, and gathering place.(ON THE ADVANCED PHOTONIX CONFERENCE CALL RICK KURTZ, IN RESPONSE TO MY QUESTIONS ADVISED THERE IS NO SPECIFIC SPECTROSCOPIC CAPABILITY ON THE ANOMALY DETECTION DEVICE. IT WILL HOWEVER, REGISTER, SUSPECTED "ANOMALIES" ON PERSONS OR MATERIAL SCANNED.)
The beta version of the device will be shipped to IQT, as early as this November. On it's last conference call API, CEO, Richard Kurtz, made it clear that API, is not being restricted by IQT, from offering this device for use in other countries and hence it will be able to market this device for use by Governments around the globe.
The prospects for wide-spread use of this new device are truly remarkable, and will help bring more public awareness to the power and promise of THz.
(If you like this post, please share it with your friends on Facebook, and other social media)
MY NOTE: AS YOU CAN SEE FROM THE COMMENTS, MY SURMISE, AND OPINION THAT THE PROPOSED ANOMALY DETECTION DEVICE COULD DETECT SMALL AMOUNTS OF RICIN MAY BE INACCURATE. DO YOUR OWN DUE DILIGENCE. THIS IS NOT AN INVITATION OR SOLICITATION TO INVEST IN ANY COMPANY!
FOLLOW-UP-I'VE JUST LEARNED THAT A DEVICE SUCH AS THE ANOMALY DETECTION DEVICE WOULD NEED SUFFICIENT QUANTITIES OF A SUBSTANCE TO DETECT A PARTICULAR SUBSTANCE. I APPRECIATE THE COMMENTS AND EDUCATION ABOUT THE CURRENT LIMITATIONS OF THz.
6 comments:
I am afraid your off the mark with the comments about Ricin and Terahertz. Ricin is a poison in minute quantities. Terahertz is not a trace detection technique like IMS, Mass Spec etc. It needs a sufficient quantity in bulk form to see either a spectra or an image. In addition for spectroscopy to work efficiently it has to be done in transmission mode. In the case of anomaly detection this is done in reflection mode were the signal is much much weaker and a full spectra is not obtained. The reflection system API are working on would only see changes in density for looking at hidden objects on clothes etc. Due to the physics it would not be able to get a reliable signature and especially for a substance that is needed in such small amounts. If you put a dose in a metal pen it would not be seen anyway and that would be plenty for any terrorist.
Thank you for your comments. As I write in bold print in the introduction to this blog, I'm not a scientist or engineer.
I do have some questions about your response.
I've included a number of blog posts which discuss the remarkable progress that THz has made in the spectroscopic examination even at the molecular level. For example read:
http://terahertztechnology.blogspot.com/2011/05/water-and-biological-molecules-probed.html
"With THz technology and computer simulations now at a stage where spectra of solvated biomolecules could be obtained and interpreted, our groups sought support from the Human Frontier Science Program to initiate a series of studies on biomolecule-solvent interactions and dynamics."
I will ask this question on the API conference call on Monday, but thanks again for your post.
http://www.sciencedirect.com/science/article/pii/S1093326308001460
Journal of Molecular Graphics and Modelling
Volume 27, Issue 5, January 2009, Pages 655-663
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doi:10.1016/j.jmgm.2008.10.005 | How to Cite or Link Using DOI Cited By in Scopus (2)
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A dynamics study of the A-chain of ricin by terahertz vibrational calculation and normal modes analysis
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References and further reading may be available for this article. To view references and further reading you must purchase this article.
Hailiang Zhanga, Eli Zukowskia, Radhakrishnan Balua and Susan K. Gregurick, a,
aDepartment of Chemistry and Biochemistry, University of Maryland, Baltimore County, 100 Hilltop Circle, Baltimore, MD 21250, United States
Received 14 August 2008; revised 21 October 2008; accepted 22 October 2008. Available online 30 October 2008.
Abstract
We studied the terahertz (THz) spectroscopy and low frequency normal modes of both apo- and holo- (adenosine monophosphate (AMP)-bound) ricin-A-chain (RTA) as a means to understand the dynamical changes that RTA undergoes upon substrate binding. The calculated THz spectra of apo- and holo-RTAs demonstrated a general intensity suppression upon substrate binding, which is attributed to the reduced number of collective motion in THz region. In normal mode analysis of RTA we find a shearing motion that is shared by both the apo- and holo-RTAs, whereas a breathing motion, and an upward hinge rising and an α-G bending characteristic motion are dampened significantly upon AMP binding, suggesting these motions are involved in the necessary flexibility of the active site. In contrast, we find a normal mode motion that separates domains I and II of RTA at the interface that is more common in the holo-protein. We hypothesized that the flexibility of the entrance of RTA can facilitate the entry of rRNA and allow the substrate to adjust its conformation and orientation prior to depurination. This process suggests an rRNA binding pathway which is supplemental the current RTA depurination mechanism.
Keywords: Ricin-A-chain; Depurination mechanism; CHARMM; Normal modes analysis; Terahertz spectroscopy
Article Outline
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Here's an abstract from 2007 demonstrating the use of time-domain THz in the trace detection of explosives.
TeraHertz Time-Domain Spectroscopy for Explosive Trace Detection
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Kong, S.G.; Wu, D.H.;
Dept. of Electr. & Comput. Eng., Tennessee Univ., Knoxville, TN
This paper appears in: Computational Intelligence for Homeland Security and Personal Safety, Proceedings of the 2006 IEEE International Conference on
Issue Date: 16-17 Oct. 2006
On page(s): 47 - 50
Location: Alexandria, VA
Print ISBN: 1-4244-0744-3
References Cited: 9
Cited by : 2
INSPEC Accession Number: 9443014
Digital Object Identifier: 10.1109/CIHSPS.2006.313311
Date of Current Version: 20 February 2007
Abstract
This paper presents Terahertz time-domain spectroscopy for stand-off detection of explosive traces. Despite several well-developed explosive detection techniques available, the detection of a small amount of explosive traces is still challenging. Terahertz spectroscopy demonstrates potential for explosive detection through unique absorption spectra pattern of various kinds of explosive materials. Terahertz waves show good penetration through many dielectric materials that are visually opaque. These characteristics promise the effectiveness of Terahertz radiation in the detection of concealed explosives
http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=4106222
I am not denying that you can see spectra of explosives or even Ricin. Its due to the vibrational modes of the materials crystal lattice. However, if you read the papers you will see this is done in transmission with all the power concentrated on pure material with no interference from other materials in the way. This does not apply in the field looking through clothes, bags etc, and most importantly in reflection as its much much harder than that. The multiple reflections you get in time domain systems cause interference to the Fourier transform when converting to a spectra so full wavelength spectra can not be obtained in reflection and also your not passing the beam “through the material” with the sensor on the other side, so it can not absorb the energy at the discreet frequencies which leads to the fingerprint. The additional effect of water vapour fingerprints in the air obscuring the signal mean that in a pracical sense spectroscopy is almost impossible to do it. Perhaps you might be able to “sense” something strange in the waveform but it will never detect and identify.
The anomaly detection is just that. Looking for anomalies within objects. Like seeing the shape of a hidden explosives belt, of a pack of drugs resin, some strange dense object under someone’s clothes or in a bag, but it could be a purse and only another technique would confirm that. Terahertz is not a “panacea” for all solutions you can think of in homeland security. Its success will depend on picking the right applications and getting them to the market. Terahertz suffered from overhype in the past and so much so that funding bodies got stung with wild promises about the technology. Terahertz has a bright future but its limitations also need to be recognised if it is truly to find its place in the market. Please don’t “overhype” the message as it only leads to disappointment when the technology or physics is just not the right solution. This article makes a lot of sense, especially paragraph 2. http://www.nap.edu/openbook.php?record_id=11826&page=5
Terahertz is starting to make a real impact but in the areas were the physics makes sense but overhype and wild promises do more harm than good.
Thanks again for your thought. Dr. Mittleman at Rice University has also written here that over-hyping terahertz is destructive to it's eventual success. Hence, I've asked readers to read your comments,
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