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In the area of illicit drugs, forensic case data have proven effective at detecting links between seizures and providing greater insights into illicit drug markets. This research explored the application of mathematical and statistical techniques to several chemical profiles of Australian methylamphetamine seizures. The main aim was to create and deliver a method that would expand the use of illicit drug profiling for strategic intelligence purposes, contributing to the fight against illicit drug trafficking. The use of comparison metrics and clustering analysis to determine links between existing illicit drug specimens and subsequent new specimens was evaluated and automated. Relational, temporal and spatial analyses were subsequently used to gain an insight into illicit drug markets. Relational analysis identified clusters of seizures central to the network. Temporal analysis then provided insights into the behaviour of distribution markets, specifically the emergence and extinction of certain clusters of seizures over time. Spatial analysis aided the understanding of the inter-jurisdictional nature of illicit drug markets. These analyses allowed for the generation of strategic intelligence relating to when and where the Australian methylamphetamine illicit drug market was the most active. Additionally, the strategic level trends identified clusters of seizures that were worth investigating further. These clusters were explored through a case study, which exploited additional chemical profiling data to provide drug market knowledge at an operational level. In turn, the intelligence produced at various levels could allow relevant law enforcement agencies to take necessary measures in disrupting markets.

© 2018 Elsevier B.V. Technology provides new ways to access customers and suppliers while enhancing the security of off-line criminal activity. Since the first cryptomarket, Silk Road, in 2011, cryptomarkets have transformed the traditional drug sale by facilitating the creation of a global network of vendors and buyers. Due to the fragmented nature of traces that result from illegal activities, combining the results of concurrent processes based on traces of different nature should provide supplementary benefit to understand the drug market. This article compares the data of the Australian virtual market (in particular data extracted from cryptomarkets) to the data related to traditional market descriptors, namely national seizures and arrests, prevalence data, shipping countries of seized post shipments as well as outcomes of specific surveys targeting users’ behaviour online. Results revealed the domestic nature of the online illicit drug trade in Australia which is dominated by amphetamine-type substances (ATS), in particular methylamphetamine and cannabis. These illicit drugs were also the most seized drugs on the physical market. This article shows that the combination of different information offers a broader perspective of the illicit drug market in Australia and thus provides stronger arguments for policy makers. It also highlights the links between the virtual and physical markets.

A rapid method was developed for the determination of monobutyltin, dibutyltin, tributyltin, monophenyltin, diphenyltin, and triphenyltin by liquid chromatography-isotope dilution-inductively coupled plasma-mass spectrometry in sediments and drinking water. All six species were eluted in less than 6.5 minutes with a binary gradient. Offline solid phase extraction was used to pre-concentrate the organotin compounds for quantification employing two calibration procedures; external standard calibration and isotopic dilution. The external standard calibration approach yielded detection limits in the range of 1.5 to 25.6 ng L−1. The method was linear over four orders of magnitude with regression coefficients greater than 0.99 and a peak area repeatability less than 4.5% RSD (n = 7) for all compounds. The isotopic dilution method was three times more sensitive with detection limits in the range of 0.5–1.2 ng L−1. Recoveries for the external calibration method were from 33–68% with % RSDs of 5.7–12.7%. The isotopic dilution method had recoveries of 70–114% with % RSDs of 1.2–2.9%. The methods were applied to sediments sampled from the Cooks River in Sydney. The isotopic dilution method provided a viable alternative to the more common analysis by gas chromatography-inductively coupled plasma-mass spectrometry for contaminated sediment without the requirement of sample derivatisation.

In further work investigating the intriguing application of diacetylene copolymers in fingermark detection, methods were developed to control (inhibit or enhance) the diacetylene polymerization reaction in fingermarks treated with a mixture of the monomers 2,4-hexadiyne-1,6-bis-(phenylurethane) (HDDPU) and 2,4-hexadiyne-1,6-bis(p-chlorophenylurethane) (HDDCPU) in acetone solution. These methods included the use of a humidity chamber to reduce the amount of background development while promoting development on the fingermark, subjecting developed fingermarks to freezing temperatures and using a solvent to remove unreacted monomer in order to inhibit the polymerization reaction. Developed fingermarks were enhanced by conventional lighting (white light, filtered light) and fast Raman mapping, which was shown to be advantageous over FTIR imaging. This study also demonstrated the applicability of diacetylene copolymer solutions in the covert detection of fingermarks on difficult surfaces. Furthermore, fingermarks were successfully developed with good ridge detail on pig skin (used as a model for human skin, a notoriously difficult surface on which to develop fingermarks).

Diatoms are the primary source of nutrition and energy for the Southern Ocean ecosystem. Microalgae, including diatoms, synthesise biological macromolecules such as lipids, proteins and carbohydrates for growth, reproduction and acclimation to prevailing environmental conditions. Here we show that three key species of Southern Ocean diatom (Fragilariopsis cylindrus, Chaetoceros simplex and Pseudo-nitzschia subcurvata) exhibited phenotypic plasticity in response to salinity and temperature regimes experienced during the seasonal formation and decay of sea ice. The degree of phenotypic plasticity, in terms of changes in macromolecular composition, was highly species-specific and consistent with each species' known distribution and abundance throughout sea ice, meltwater and pelagic habitats, suggesting that phenotypic plasticity may have been selected for by the extreme variability of the polar marine environment. We argue that changes in diatom macromolecular composition and shifts in species dominance in response to a changing climate have the potential to alter nutrient and energy fluxes throughout the Southern Ocean ecosystem. © 2013 Sackett et al.

In 1979, Miller and Patel showed that a solution containing two diacetylene monomers, 2,4-hexadiyne-1,6-bis(phenylurethane) (HDDPU) and 2,4-hexadiyne-1,6-bis(p-chlorophenylurethane) (HDDCPU) could be used to develop latent fingermarks on a non-porous surface. In the current work, the same mixture (HDDPU:HDDCPU = 10:1, in acetone solution) was used to develop fingermarks on a wide variety of surfaces, both non-porous and porous, including paper. An airbrush system was optimized for the application of the reagent solution. Once the solution evaporates on a surface, the monomers co-crystallize in different ways, depending upon a number of factors, including the surface residue. " Active" co-crystallization leads (with heat or radiation) to the formation of purple polymer, while " inactive" crystallization results in a non-polymerizable white deposit. Fingermark contrast was achieved as a result of active co-crystallization (giving purple polymer) in either the ridges or the furrows, depending upon the surface and other factors. A general observation (supported by spot tests with linseed oil, salt and amino acid solutions) was that on paper, oily materials are more likely to lead to the formation of the purple polymer, while the presence of water inhibits polymerization. However, these observations are not consistent across all other substrates. It is hypothesized that water disrupts hydrogen bonding between diacetylene molecules, and thus prevents the topochemical polymerization of the diacetylenes, which occurs in the solid state between favourably aligned monomers. An interesting observation was the development of fingermarks deposited on paper that had already been treated with the diacetylene reagent. © 2011 Elsevier Ireland Ltd.