Social detritus

'The daily press is the evil principle of the modern world, and time will only serve to disclose this fact with greater and greater clearness. The capacity of the newspaper for degeneration is sophistically without limit, since it can always sink lower and lower in its choice of readers. At last it will stir up all those dregs of humanity which no state of government can control.'

Soren Kierkegaard (1813-1855)

Soren Kierkegaard, a Danish philosopher and theologian, expressed this opinion in The Last Years, a collection of his journal entries between 1853 and 1855. How apt they were in the middle of the 19th Century, I do not know, but now, over 150 years later, they can have rarely resonated with such truth.

During the course of the last year we have, as always, seen a number of examples of journalists taking their journalistic license just a little bit too far. But, what we all witnessed thoughout the summer regarding the end of the world as soon as the LHC was switched on at CERN, made feeding time in the lion enclosure look like the height of hout-couture!

This problem of media attention for all the wrong reasons was similarly faced by astronomers 5 to 10 years ago. Pioneering work on the Cretaceous-Teriary impact by Walter Alvarez and others cemented the idea of cataclysmic asteroid impacts causing mass extinction events, in turn paving the way for enormous summer blockbusters such as Armageddon and Deep Impact. In the wake of these attention grabbers, every discovery of an asteroid with an Earth crossing obit (known as an NEOs - Near Earth Object) gained pages of dedicated coverage in the world's media. The end of the world was, seemingly, at hand.

In the short-term such publicity can be good for the scientists involved, but in the long-term its effect on the science can be disastrous. The general public have a relatively short attention span when compared to your average scientific experiment. Don't get me wrong, this isn't the scientist inside me coming over all pompous and considerably better than thou, rather simply stating the fact that the public struggle to grasp the immense timescales involved in most scientific project, nor the general scientific adage of 'so-and-so being correct within errors'.

With the NEOs this is particularly apparent; when was the last time you saw a newspaper report of an asteroid getting all snugly with the Earth in a couple of hundred years time? Just because the press coverage has died down doesn't mean the chance of us being wiped out by a lump of rock and metal hurtling towards us from the icy depths of the solar system have diminished, quite the contrary. One will hit us sooner or later, and chances are we might not even see it coming as it approaches us from perihelion (closest approach to the Sun) and is therefore lost in the blinding glare of our dear, little star. The lack of news is simply a reflection of the rapidly waning interest.

I, for one, hope that CERN and the LHC does not suffer a similar fate. Although it will, in all likelihood, take some 5+ years to get meaningful results the team are confident enough to publish, the questions it could answer are enormous. However, somehow, sadly, I think it has already begun. Indeed, one could say it had already begun the moment the world didn't end...even if that was just a rediculous piece of journalistic fiction.

Alternative famine remedy...

Recently I came across a paper published in the September 1920 issue of the journal Nature under the rather presumptuous title; 'The Drying up of South Africa - and the Remedy'. This interesting paper (more of a comment, really) talks about the eternal struggle between Mankind and Nature (as in the hippy-ish force, not the journal!), opening with the paragraph:

'Whilst Man of all races and skin-colours is once more involved in fractricidal quarrels - how Superior Intellegences in more advanced spheres must grin as they watch our wars against one another through super-telescopes or by aethereal telegraphy! - Nature is making one more effort to get rid of man. This time through Drought. She has seemingly hated everything that rose above the mediocre on this planet, whether it was in fish shape, or the fish-saurian, the dinosaur, the struthious bird, the ungulate mammal, or the brain-worker, Man. She tried to nip us in the bud by reviving the Ice ages which she had used for other destructive purposes in the pre-Cambrian, Devonian, Permian, and Jurrasic periods. But this succession of cold spells only braced Northern Man to greater efforts and greater triumphs, and sent Southern Man to grapple with the tropics, and to digest and partly overcome their germ diseases. Now the tropics, and above all the sub-tropical regions are being threatened by drought. The desert is spreading in sub-tropical North America, in tropical South America, in temperate and sub-tropical Asia and eastern Europe, in northern and north-central Africa, and in that prolongation of the African continent which lies beyond the Zambezi and Kunene Rivers.'

Quite a rant, I know! Wait until you see the last paragraph:

'Man must give up internecine warfare and unite all his forces to defeat his arch-enemy, Nature. He must melt the ice at the North and South Poles, and put a stop to the spread of desert conditions in Asia, Africa, Australia, and the Americas.

H.H. Johnston'

'...unite all his forces to defeat his arch-enemy, Nature.' For some reason I now have an image of Nature in my head that's a cross between Brittania and the classical Victorian image of Queen Boudica.

Well, whether by design or not, we seem to be trying to do what he suggests, although somehow I don't think it's working quite how he imagined...

How proxy is a proxy? - Part II

So, I believe that last time I threatened to, for once, have a series of evolving posts that gradually elucidate on a single topic. Henceforth, here is round two.

As a reminder, last time I posed the question:

How accurate are experiments where non-human, proxy cadavers are used?

In particular, I'm considering experiments where we want to use existing acoustic technology to image submerged cadavers.

To start with, lets think about precisely what we're going to be imaging with the acoustic returns. Sounds simple, doesn't it?! Sadly, as with almost everything to do with acoustics, simple questions tend to result in complex answers.

In order to image something using sound, it needs to present a measurable change in acoustic impedance (i.e., basically a measure of the strength to which the material resists the passage the sound wave) to it's immediate surroundings. The human body is generally considered to consist of 60 -70 % water, suggesting that a cadaver sitting on the seabed, lakebed, or riverbed will tend not to offer as strong an acoustic target as, say, the sediments on which it is resting because it closer resembles the water around it than the sediments do.

However, the acoustic backscatter from a target (the sound which travels from the source to the object and is reflected back towards the source again) is the combined response of two processes:

1. Surface scattering: the energy reflected back by the water/cadaver interface.

2. Volume scattering: the energy reflected back from within the target.

Of these, the volume scattering is the one we're particularly interested in. As I said earlier, the surface scattering will not be very strong for a cadaver. The volume scattering, on the other hand, will be. This is because, during decomposition, gas builds up within the tissue and internal cavities of the cadaver. This gas will present a very strong change in acoustic impedance.

So, when we want to acoustically image a cadaver, we would expect the dominant acoustic signature to be from the build up interstitial gas as a result of decomposition.

How proxy is a proxy? - Part I

As I've mentioned in a blog a couple of months ago, Piggy hide and seek, I've recently been looking into the idea of using shallow water marine geophysical techniques in helping Law Enforcement Agencies conduct underwater body searches. Going through the frantic research process involved with writing any kind of research proposal, a particularly interesting thought occurred to me, namely:

How accurate are taphonomic experiments where non-human, proxy cadavers are used?

In certain states of the USA it is possible to use human cadavers when people have donated their body to science, or their body remains unclaimed. This has enabled researchers at the University of Tennessee's Anthropological Research Centre, in Knoxville, to setup their 'Body Farm', where human cadavers are placed in a variety of environmental conditions and their decay monitored over a period of days, weeks, months, and sometimes years. As a result of the ground-breaking research conducted at Tennessee, other body farms have now sprung up in Western Carolina University and Texas State University, although on considerably smaller scales.

The work undertaken by these institutions has been truly astonishing, advancing forensic entomology immensely. Without this work there must be thousands, perhaps hundreds of thousands, of homicides the world over that would never have been solved. However, outside of these specific locations, the vast majority of people trying to undertake research in this, or related, fields have to rely of using proxy cadavers, normally domestic pigs. This leads to the question of how accurately a pig cadaver can imitate a human one? Taphonomically they have been shown to be very, very similar; their skin is close enough to ours for use in skin grafts for burns victims, whilst, also being omnivores, they have much the same gut bacteria, leading to a decomposition progression that very closely mimics our own.

This is all well and good for taphonomic and forensic entomology studies of beetle or fly larvae colonization, etc, but for our purposes, where we want to image the acoustic properties of the cadavers, can we truly say the same?

This is something I'm, hopefully, going to explore in the next few blogs by discussing the physics behind the variety of acoustic profilers that can be used. In this way, it should be possible to see where the potential differences between the different cadavers could result in different observations.

The Obama-wagon...quick, jump!

Firstly, and probably most importantly, congratulations to Senator Obama on his resounding victory Tuesday evening. Secondly, congratulations America!

It was quite a surreal evening for me. I attended my first ever 'Election Party' (I'm not sure what it says about me that it was for an American Election rather than a British one, but...). Throughout the evening there was a lot of talk about how, if Obama got in, people would feel 'proud to be American again', which says a lot for the damage our friend George W. has done to international relations on all levels. However, the best comment of the evening, I think, came when someone said:

'We've really dodged a bullet by avoiding electing Palin as Vice President.'

I couldn't agree more, it's hard to imagine what could be worse that having the gun-toting creationist loitering in the wings, just in case something happened to McCain. I have to admit, though, there is a part of me that feels sorry for Senator McCain. The guy is not a bad politician, and probably wouldn't have made a particularly bad President, but suffered because somehow his party decided Sarah Palin would make a great running-mate!

However, what has grabbed my attention most about the immediate outfall from the election result, is the level of childishly cynical hero worship that has swept around the political world. Nothing describes this better than the pitiful exchange between Gordon Brown and David Cameron in the House of Commons yesterday.

What is more pathetic than two grown men fighting it out to be associated with Senator Obama's victory? Why is it necessary - is the result of the US election really going to influence British voters in their choice of who they will vote for in our forthcoming election? Had the elections happened the other way around (which they might well have), do they really think that Obama and McCain would have reciprocated and been fighting tooth and nail as to whose campaign closest resembled that of the British PM? I think not!

After all the comments on the blog-o-sphere and articles in newspapers and news websites in the UK criticizing American politics over last few years, on the evidence of this we should perhaps be looking a little closer to home!