Long-tail events

This final chapter provides a brief overview of how offshore safety management is changing, and what developments could plausibly occur over the next few years. Also discussed in this chapter are the topics of leadership and long-tail events. Some concluding thoughts to do with leadership and the role of regulations are provided. 

The Fukushima event heightens awareness of black swan or long-tail events, as discussed in Chapter 8. 

The natural response would be for companies to make the necessary investments to protect themselves against long-tail events, but, in the words of Taleb ... 

This model for subdiffusion in the external force field F(x) — — ( ) provides a basis for fractional evolution equations, starting from Langevin dynamics that is combined with long-tailed trapping events possessing a... 

The six aligned sequences in Fig. 1 were used to build amino add parsimony trees by PROTPARS in PAUP.13 An exhaustive search of the 105 alternative unrooted trees was performed the resulting distribution of possible trees was skewed14 positively, with a long tail (not shown) containing the shortest tree. This shortest unrooted tree (Fig. 2) requires 601 amino acid replacements the next shortest tree requires 625 events. In this case, the most parsimonious tree appears rather trustworthy. 

Defining the "age" of the Earth is a difficult task, for the age of the Earth may mean a number of different things. Harper and Jacobsen (1996) have shown that the age of the Earth may be defined as either the time the solar system began (T0) or as the time at which accretion ended (TE). However, both approaches are problematical, for the solar system began before the Earth was formed, and yet the end of accretion is very difficult to define, since the accretion process had a long tail. They suggest that a useful compromise is to define a mean accretion age for the Earth, as the time when 64% of the planetary mass had accreted. Here the main events in the accretion... 

The time distribution of the antineutrino burst is set by the half-lives of the fission products. These peak at relatively short times, ranging firom a few milliseconds to a few seconds, with a long tail extending out to very long half-lives. Figure 3 shows an approximate time distribution of the events. The mean lifetime is about 2.5 seconds. ... 

Eukaryotic mRNAs often have long 3 untranslated sequences— sequences that follow the stop codon for the protein they encode. These mRNAs generally conclude with a sequence of up to 200 adenosines, the polyadenylic acid (polyA) sequence at the 3 end. This sequence isn t coded by the DNA template for the gene it is added post-transcriptionally. Not all mRNAs are polyadenylated. For example, histone mRNAs lack polyA tails. Polyadenylation seems to play a role in regulating the stability of mRNAs. An early event in the breakdown of some mRNAs is the removal of their polyA tails. 

It is also unclear whether archaeal mRNAs can be cotranscriptionally or post-transcriptionally modified. Polyadenylated RNAs have been identified in several archaea [21-23], the poIy(A) tails being quite short in methanogens [22] and rather long in the halophiles and the crenarchaeota [21-23]. However, evidence that they are indeed mRNAs is lacking. In any event Poly(A)+ RNAs are not capped in Methanococcus vannielii [22]. 

Meanwhile, her fleetmate Columbus was making her ill-fated bid to make it home from Vera Cruz, Mexico, where she had sought sanctuary after her Caribbean pleasure cruise was interrupted by the outbreak of hostilities. Prior to sailing for home, the Columbus master had his slii] darkened in like fashion to the Bremen but, in addition, the tops of her funnels were painted black. In the event none of this particularly aided the ship. On her voyage north she hugged the American coast for as long as she could, tailed by a succession of American warships, but, on 19 December, immediately upon leaving the safety of neutral American waters, she was intercepted by the destroyer HMS Hyperion and was scuttled by her crew. 

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