Wednesday, 13 November 2013

Science Week I - The Police

It's Science Week in Ireland and The Institute is contributing and and benefiting a little.  On Friday afternoon a couple of Detective Sergeants came round from the Garda Technical Bureau to talk to the students.  Some of whom are bound to be interested because their degree is Biosciences with Forensics.  We're gradually covering the bases having had the State Pathologist and the Governor of Mountjoy Gaol here before.  Years ago, the department in which I was working had a professorial chair to fill and invited all those on the short-list to give a job-seminar to see a) whether they were capable of presenting to an audience and b) whether their research had anything going for it.  One of the candidates went on (and on and on) for an hour and forty minutes about his stressed mice.  As we staggered out of there with numb buttocks, I said that I fervently hoped we'd hire someone with better editing sense and more consideration of the value of other people's time.  We didn't.

Our two guests went over the limit to the same extent as the Professor and I brought shame upon The Institute by a) falling asleep at minute 70 and b) snoring at minute 75.  Thanks to the quick reactions (prod!--->) of my HoD the snickers were limited to our immediate vicinity. It could have been worse. At about the same time as that earlier job seminar, a prestigious event quatercentenary? 50th anniversary? at my alma mater was celebrated with a day of internationally acclaimed speakers in the biggest auditorium in the University.  After a generously lubricated lunch, the Professor of Genetics fell extravagantly asleep in the second row from the front and, as nobody was sitting near him, he continued to snore through the rest of the talk and everyone pretended that it wasn't happening.  That convinced me that there was no essential difference in the bystander effect between the English and the Irish when in a crowd.

Mais revenons-nous a nos flics.  Apart from going on too long, it was a pretty good perf, especially if you've never seen the analysis of blood-spatter before.  As a fainter, I knew enough to look fixedly at my hands while that section was going on (and on and on) so I didn't cause a real commotion like I did in my chain-saw handling course in 1998.  What I have learned:
  • the number of IEDs (improvised explosive devices - pipe-bombs) has gone from about 3 a year in 1970 to 3 a day now.
  • mitochondrial DNA is insufficiently discriminatory for forensic evidence:  there are only about 100 detectable differences in the DNA sequence, so each variant is shared by 40,000 other people.
  • the erased uniquely identifying 17 digits stamped on a car chassis can be recovered with Fry's reagent because the crystalline structure underlying metal is deformed by the stamping process
  • clandestine buried bodies can sometimes be found with GPR ground-penetrating radar; GRS ground-resistance surveying; and Magnetometry.
  • candles can cause fatal house-fires
  • GSR gunshot-residue is labile and so needs to be analysed within hours of the crime
  • Western ammunition is rich in lead Pb, barium  Ba and antimony Sb with lesser quantities of aluminium Al, zirconium Zr and titanium Ti
  • whereas Eastern-bloc ammo has more mercury Hg, tin Sn, antimony Sb and lighter elements.  Mercury having been banned from ammunition in the West because of its toxicity!
  • that at least one of our students has served in the armed forces because he knew as much about guns as the Gun-garda.
Verdict: worth going to hear and I'm sorry I nodded off.  It won't happen again, officer.

1 comment:

  1. mercury in bullets banned because of its toxicity???

    ReplyDelete