ArmsControlWonk.com

With the discovery of a new and deadly flu virus in Mexico that might become a worldwide pandemic, I wanted to familiarize myself with the terminology used and bandied about so much in the media. This is the flu naming conventions such as H1N1 or H5N1 strains we are starting to hear so much about. (By the way, this qualifies for armscontrolwonk.com because the public health response to a pandemic is the same whether or not it is caused by human action.)

So here is a quick tutorial on Flu Terminology that I’ve learned:

Flu viruses are categorized by two surface molecules: the neuraminidase (from which the N comes from) and the haemagglutinin molecules (where we get the H). Neuraminidase and haemagglutinin are characterized by the response of antibodies to them. For human influenza viruses the convention is:

—all those in circulation before 1957 are termed H1N1 viruses

—those arising between 1957 and 1968 are known as H2N2

—those present since 1968 (and not previously named) are known as H3N2 (my reference material dates from 2002 so perhaps more have arisen.)

Other strains, such as H5N1, are not originally human viruses though the big danger is that they will jump from birds, swine, or horses to humans.

Neuraminidase has been described as a “mushroom” shaped molecule but with a square head attached to a long thin stalk. It is associated with the release of viruses produced in a host cell. In fact, neuraminidase specific antibodies will prevent their release but will not prevent the original infection of the cell. There are five separate sites on the neuraminidase molecule that antibodies bind to. A single amino acid change at any of these sites makes the virus invisible to the antibodies that had previously attached quite well.

Hemagglutinin is a triangular rod-shaped molecule and is associated with the virus’ binding sites in the host organism. For instance, human and swine haemagglutinin prefer one type of receptor molecules and bird flu viruses prefer a different one.

Interestingly, if a cell is infected with two different flu viruses (such as H1N1 and H2N2) then the virus genetic material can be rearranged in the cell so that the released viruses include mixes like H1N2 and H2N1 surface molecules.

Most of this information comes from the various papers in “Influenza” edited by C.W. Potter. If I’ve made any mistakes, I’m sure biologically oriented wonk-readers will let me know and correct the errors in the comments.

[Geoff takes pains to justify his post about pandemic influenza, but this is a topic we have discussed before. Pandemic influenza is the sort of non-deliberate threat threat that requires “cooperation between potential enemies”, a solution set that encompasses the canonical definition of arms control — Jeffrey]

If you are anything like me, you suffer a death of a thousand cuts when you see something on GoogleEarth and want to know how tall it is. For instance, you can measure the diameters of Iran’s heavy water exchange columns (3.5 m) but if you could only measure their height then maybe you could tell what their capacity was. It would seem a simple thing for Google to just to tell you the date and time of any individual pixel on a scene and then you could calculate the sun’s elevation. After all, they know which picture is contributing to each part of the Earth’s surface and each picture has a time stamp embedded in its geographical information. Be that as it may be, they don’t seem to want to do it.

But there is often—not always, but often—a date stamp on the bottom of the screen. I thought; why not use what ever you are interested in measuring as a Sun Dial to tell the “time” of the image? That’s exactly what my program calculateHeightFromShadow does! You can download it for free at my website’s download page. (Unfortunately, you also have to download and setup GUI_missileFlyout before you can use this height measuring program. This is because the MATLAB run library has to be on your computer and my website does not have the storage to allow me to put both up independently.)

So, what about those Iranian heavy water exchange columns? They are approximately 50 m high. (And the final distillation tower is 130 m tall.) I’ve noticed, while checking out this program against various landmarks, that there is an approximately a 10% error associated with this measurement. This seems to be dominated by unlevel ground effects (the shadow terminating on buildings or on a hill side) and problems picking out the right starting point for the. Perhaps surprisingly, this is really difficult! At least if you want to do better than 10%.

There is also something else to note. I’ve started to wonder about some of those dates listed by GoogleEarth. I’m not sure, but I’m beginning to think some of those dates are wrong, or at least don’t apply to some of the scenes they are linked to. However, this seems to be true only for Western cities where there is plenty of coverage and perhaps they aren’t particularly concerned about getting the date right. I’ve checked the program against the Eiffel Tower, the Arc de Triomphe, and the Xichang SLC’s service tower; all of which I know the heights for and I get within +-10%.

I also tried checking it against the St. Louis Gateway Arch but this has proven to be very difficult, either because its difficult to judge the correct spots to measure with a curved arch or, just perhaps, it is the wrong date on GoogleEarth. After all, the date stamp says it’s June, but some of the trees in the area are clearly without leaves. If I use a March date, then I get a reasonable height for the Arch.

By the way, you can see an amusing example of the problems associated with knitting together different scenes if you look at the bridges across the Mississippi just to the East of the Arch; in particular, look at the Martin Luther King Bridge. I’d say it was because the camera “tilt” was different between the two different images while looking at elevated objects, but I’ve seen the same thing on surface roads.

Have fun!

ps It only works with windows, Sorry Mac users!

In Europe, Britain’s National Audit Office has released a report on the United Kingdom’s Future Nuclear Deterrent Capability. It is an interesting read. The main conclusion is that:

There is a challenging timetable to meet if continuous at sea deterrence is to be maintained. The critical path for provision of a future deterrent capability is the delivery of the nuclear-powered submarine platform in time to meet an in-service date of 2024. But there are also possible time constraints from other areas of the programme. There is currently little scope for incorporating time contingency in the overall programme to deal with slippage in any of these areas.

The Office also says that a replacement cannot be made without the help of the United States, which produces its own sets of challenges. In particular, the project timeline becomes quite inelastic.

Have a read here.

As part of the Wonk’s public service role, let me bring to your attention an outstanding resource letter, “Physics and Society: Nuclear Arms Control”, that was published by Alex Glaser and Zia Mian in the January edition of the American Journal of Physics (vol. 76, no. 1, pp. 5—14 to be precise). It’s a great list of key arms control texts—but, unfortunately, I think it is only available to AJP subscribers.

Actually, this reminds me of a (vaguely) funny story. I ordered a copy of Alan Krass’ excellent book Verification: How Much Is Enough? off Amazon Marketplace last year. And, judging by the inscription in the front cover, the copy I got used to belong to noted BW and CW arms control expert Raymond Zilinskas! Makes you realize what a small world the arms control community is.

UPDATE: Yes, the AJP article is freely available—from here to be exact!

I came across this really cool resource today and thought I’d share it with my fellow wonks. It’s the complete library of reports prepared by the Congressional Office of Technology Assessment, with links to the full text of each report.

Many of the OTA reports are classics in the field of nonproliferation, such as the June 1977 wonkfest Nuclear Proliferation and Safeguards, which weighs in at more than 1300 pages (including appendices). Enjoy.

OTA was among the many sensible governmental resources that Newt Gingerich’s so-called “Republican Revolution” put before a firing squad in 1994-1995. Kudos to the University of North Texas’s CyberCemetary Project for making these resources so readily available.

Jeffrey adds at 1:40 pm that Congressman Rush Holt has led the fight to restore OTA.