Harry Pirie-Gordon: Historical research,journalism and intelligence gathering in the Eastern Mediterranean (1908–18)

British scholars were active in the Levant during the years leading up to the outbreak of the First World War. Harry Pirie-Gordon toured medieval castles in the region during the spring of 1908 under the auspices of the British School at Athens; T.E. Lawrence used his maps in the following year. Pirie-Gordon continued to travel widely in the Near East as a member of the Foreign Department of The Times and was involved with the survey of the Syrian coastline around Alexandretta. He was commissioned in the RNVR in 1914 and took part in the raid by HMS Doris on Alexandretta. Pirie-Gordon served in an intelligence capacity at Gallipoli before returning to Cairo to work with David Hogarth. In 1916 he was involved with the occupation of Makronisi (Long Island) in the Gulf of Smyrna. Later that year he took charge of the EMSIB operation at Salonica until its purge in early 1917. Pirie-Gordon returned to the Arab Bureau in Cairo and took part in the Palestine campaign.     

An investigation of the rigor of interpretation rules for STRs derived from less than 100 pg of DNA

By increasing the PCR amplification regime to 34 cycles, we have demonstrated that it is possible routinely to analyse <100 pg DNA. The success rate was not improved (without impairing quality) by increasing cycle number further. Compared to amplification of 1 ng DNA at 28 cycles, it was shown that increased imbalance of heterozygotes occurred, along with an increase in the size (peak area) of stutters. The analysis of mixtures by peak area measurement becomes increasingly difficult as the sample size is reduced. Laboratory-based contamination cannot be completely avoided, even when analysis is carried out under stringent conditions of cleanliness. A set of guidelines that utilises duplication of results to interpret profiles originating from picogram levels of DNA is introduced. We demonstrate that the duplication guideline is robust by applying a statistical theory that models three key parameters - namely the incidence of allele drop-out, laboratory contamination and stutter. The advantage of the model is that the critical levels for each parameter can be calculated. This information may be used (for example) to determine levels of contamination that can be tolerated within the strategy employed. In addition we demonstrate that interpreting one banded loci, where allele dropout could have occurred, using LR=1/2f(a) was conservative provided that the band was low in peak area. Furthermore, we demonstrate that an apparent mis-match between crime-stain and a suspect DNA profile does not necessarily result in an exclusion. The method used is complex, yet can be converted into an expert system. We envisage this to be the next step.     

Ketamine in non-hospital and hospital deaths in New York City

We reviewed all ketamine-positive deaths (87) examined at the New York City Office of Chief Medical Examiner over a two-year period (1997 to 1999). There were 15 non-hospital deaths with 12 due to acute multidrug intoxications, one due to sarcoidosis, and two due to physical injury (blunt and thermal). In no instance was a fatal intoxication caused exclusively by ketamine. Opiates (10/15), followed by amphetamines (7/15) and cocaine (6/15), were the most frequent co-intoxicants. Ethanol was found in only one death. The race of all decedents was white and the majority were men (11/15) between the ages of 18 and 30 years. The remaining 72 instances of positive ketamine findings were hospital deaths following surgical procedures or burns.     

DNA Commission of the International Society of Forensic Genetics (ISFG): an update of the recommendations on the use of Y-STRs in forensic analysis

The DNA Commission of the International Society of Forensic Genetics (ISFG) regularly publishes guidelines and recommendations concerning the application of DNA polymorphisms to the problems of human identification. A previous recommendation published in 2001 has already addressed Y-chromosome polymorphisms, with particular emphasis on short tandem repeats (STRs). Since then, the use of Y-STRs has become very popular, and a numerous new loci have been introduced. The current recommendations address important aspects to clarify problems regarding the nomenclature, the definition of loci and alleles, population genetics and reporting methods.     

Analysis of artificially degraded DNA using STRs and SNPs--results of a collaborative European (EDNAP) exercise

Recently, there has been much debate about what kinds of genetic markers should be implemented as new core loci that constitute national DNA databases. The choices lie between conventional STRs, ranging in size from 100 to 450 bp; mini-STRs, with amplicon sizes less than 200 bp; and single nucleotide polymorphisms (SNPs). There is general agreement by the European DNA Profiling Group (EDNAP) and the European Network of Forensic Science Institutes (ENFSI) that the reason to implement new markers is to increase the chance of amplifying highly degraded DNA rather than to increase the discriminating power of the current techniques. A collaborative study between nine European and US laboratories was organised under the auspices of EDNAP. Each laboratory was supplied with a SNP multiplex kit (Foren-SNPs) provided by the Forensic Science Service, two mini-STR kits provided by the National Institute of Standards and Technology (NIST) and a set of degraded DNA stains (blood and saliva). Laboratories tested all three multiplex kits, along with their own existing DNA profiling technique, on the same sets of degraded samples. Results were collated and analysed and, in general, mini-STR systems were shown to be the most effective. Accordingly, the EDNAP and ENFSI working groups have recommended that existing STR loci are reengineered to provide smaller amplicons, and the adoption of three new European core loci has been agreed.     

New multiplexes for Europe-amendments and clarification of strategic development

Recently, the ENFSI/EDNAP groups issued advice on the design of the next generation of STR multiplexes in order to encourage standardisation within Europe. As the result of collaborative experimentation within the EDNAP group, we demonstrated that the low molecular weight STRs had substantial benefits to detect degraded samples. We subsequently recommended adoption of three new mini-STR loci to improve the success rate of degraded DNA markers, concurrent with the reduction in size of the existing STR markers in current use. This also improves the discriminating power of the system which is important to improve the power of national DNA databases. Subsequent discussions have occurred with manufacturers and members of the ENFSI/EDNAP groups. Because significant time and investment is required to develop new multiplexes of 13+ STR loci, manufacturers indicated that it would be preferable to adopt a staged approach. Two differing, but parallel strategies have now emerged. The first strategy employs a 13 STR loci multiplex incorporating three mini-STRs into the current multiplex test. The second strategy employs a multiplex of six high molecular weight STRs (in current use), modified to provide smaller amplicons combined with an additional two loci of high discriminating power. Eventually, the two strategies will converge to provide a single multiplex of 15 STR loci. The process will be guided by the ENFSI/EDNAP groups.     

Dynamic Tempered Transitions for Exploring Multimodal Posterior Distributions

George Casella Department of Statistics, University of Florida, Griffin-Floyd Hall, P.O. Box 118545, Gainesville, FL 32611 e-mail: casella{at}stat.ufl.edu Multimodal, high-dimension posterior distributions are wellknown to cause mixing problems for standard Markov chain MonteCarlo (MCMC) procedures; unfortunately such functional formsreadily occur in empirical political science. This is a particularlyimportant problem in applied Bayesian work because inferencesare made from finite intervals of the Markov chain path. Toaddress this issue, we develop and apply a new MCMC algorithmbased on tempered transitions of simulated annealing, addinga dynamic element that allows the chain to self-tune its annealingschedule in response to current posterior features. This importantfeature prevents the Markov chain from getting trapped in minormodal areas for long periods of time. The algorithm is appliedto a probabilistic spatial model of voting in which the objectivefunction of interest is the candidate's expected return. Wefirst show that such models can lead to complex target formsand then demonstrate that the dynamic algorithm easily handleseven large problems of this kind.