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Shingleback lizards (Tiliqua rugosa) are among the most trafficked native fauna from Australia in the illegal pet trade. There are four morphologically recognised subspecies of shinglebacks, all with differing overseas market values. Shinglebacks from different geographic locales are often trafficked and housed together, which may complicate identifying the State jurisdiction where the poaching event occurred. Additionally, shinglebacks can be housed and trafficked with other species within the same genus, which may complicate DNA analysis, especially in scenarios where indirect evidence (e.g. swabs, faeces) is taken for analysis. In this study, a forensic genetic toolkit was designed and validated to target shingleback DNA for species identification and geographic origin. To do this, field sampling across Australia was conducted to expand the phylogeographic sampling of shinglebacks across their species range and include populations suspected to be poaching hotspots. A commonly used universal reptile primer set (ND4/LEU) was then validated for use in forensic casework related to the genus Tiliqua. Two additional ND4 primer sets were designed and validated. The first primer set was designed and demonstrated to preferentially amplify an ∼510 bp region of the genus Tiliqua over other reptiles and builds on existing data to expand the available phylogeographic database. The second primer set was designed and demonstrated to solely amplify an ∼220 bp region of T. rugosa ND4 over any other reptile species. Through the validation process, all primers were demonstrated to amplify T. rugosa DNA from a variety of sample types (e.g. degraded, low quality and mixed). Two of the primer sets were able to distinguish the genetic lineage of T. rugosa from the phylogeographic database. This work provides the first forensically validated toolkit and phylogeographic genetic database for Squatmate lizards.

Reptiles are the most trafficked live taxa in the illegal wildlife trade, in part due to their popularity as an exotic pet. Current methods used to detect these illegally trafficked animals are limited. This study optimised the collection and analysis parameters associated with volatilome collection that will set the foundation for targeted odourant detection methods. This study determined that the dual sorbent type (Tenax® TA and Carbograph 5DT) in combination with 20-min sampling times and 15-min sampling intervals collected the most reproducible reptile volatilome profiles. It was also determined that desorption methods with mid-range desorption flows (20 ml/min), trap temperatures (-15 °C), and mid-range trap desorption (25 ml/min) were most effective in retrieving collected reptile volatilomes. Two-dimensional gas chromatography coupled with time-of-flight mass spectrometry was used for analysis, where combined Rxi-624 Sil MS (mid-polar) first dimension and Stabilwax® (polar) second dimension column sets were selected as the most effective columns for analysing reptile volatilomes. The resultant data collected and analysed using these parameters demonstrated that individual volatilomes from three reptile species were distinct using principal component analysis. In addition, this work highlighted the need for more rigorous statistical methods to determine reptile biomarkers and which compounds most significantly influence volatilome profiles between species.

Modelling clays are utilised by artists for their malleable properties. One of the challenges in managing collections containing such materials is the variety of commercial compositions available and, therefore, the variation in the requirements for storage and maintenance of such artefacts. The Art Gallery of New South Wales in Australia is responsible for the care of a range of artworks that contain modelling materials, some of which show detrimental property changes and there is concern for the longevity of such works. The aim of the current research is to determine the compositions of the modelling materials utilised in works produced by different artists in the gallery’s collection. Infrared spectroscopy was used to identify the main constituents of samples collected from the works of four different artists and a variety of material types were determined. Oil-based, air-hardening and polymer clays of varying composition were identified in the survey of artworks. Signs of deterioration in particular artworks were able to be characterised using spectroscopy, with the mechanisms identified including loss and oxidation of the oil component. Where a polymer clay was chosen by one artist, the distortion of the artwork was due to flow of the material over time and demonstrates the need for an understanding of the long term properties of the materials being used. The study has highlighted the need for conservators to have a detailed understanding of modelling materials to ensure the longevity of artworks containing this class of materials.

© 2019 This neutron diffraction study of deuterated tripalmitin has provided further insight into a forensic observation of the crystallisation of lipids under high-shear conditions. To achieve this, an experimental set up was designed to enable simultaneous rheological data from a Couette cell to be recorded with neutron powder diffraction, enabling the influence of shear on the polymorph transformation on cooling to be monitored in real time. Tripalmitin was observed to directly transform from a liquid phase to a β polymorph under the influence of shear. Although the liquid to β transition was not observed to be influenced by shear rate, the degree of crystallinity, qualitatively denoted by an increase in the sharpness of the diffraction peaks, was observed at higher shear rates. Evidence is also presented that the rate of cooling influences the ordering in the β-polymorph produced in zero shear conditions.

© 2019, Springer Science+Business Media, LLC, part of Springer Nature. Previous studies of fabric degradation have shown promising results for post-mortem interval estimations based on differences in the degradation states of clothing in the presence of decomposing remains. It is crucial to determine if a body was present when using the degradation state as an indicator of time since death. For this study, fabric samples from buried pig remains were collected and analyzed using attenuated total reflectance Fourier transform infrared spectroscopy and chromatography- mass spectrometry. Three different fabrics were investigated; 100% cotton, 100% polyester and a polyester-cotton blend. Distinct visual changes were observed between the experimental and control graves, with the fabrics in the control grave degrading more rapidly. There was also a difference between the fabric types, whereby the natural fabrics degraded much faster than the synthetic ones. Principal component analysis was used to determine that the cotton control samples could be statistically separated based on their degradation state. The presence of lipids and proteins were useful for separating “wetter” graves from those drier in nature as well as the control graves. Clothing evidence was demonstrated to provide quantitative time since death information, as well as indicating the decomposition site in the event of intentional or unintentional movement.

The conservation of polymer-based cultural heritage is a major concern for collecting institutions internationally. Collections include a range of different polymers, each with its own degradation processes and preservation needs, however, they are frequently unidentified in collection catalogues. Fourier transform infrared (FTIR) spectroscopy is a useful analytical tool for identifying polymers, which is vital for determining storage, exhibition, loan and treatment conditions. Attenuated Total Reflection (ATR), and External Reflection (ER) are proven effective FTIR sampling techniques for polymer identification and are beginning to appear in conservation labs. This paper evaluates and optimises the application of these two FTIR techniques to three-dimensional plastic objects in the museum context. Elements of the FTIR measurement process are investigated for 15 common polymers found in museum collections using both authentic reference sheets, and case study objects to model for surface characteristics. Including: use of the ATR and ER modules, the difference between clamping and manually holding objects in contact with the ATR crystal, use of the Kramers–Kronig Transformation, signal-to-noise ratios for increasing number of co-added scans, resultant time taken to collect each measurement, associated professional, health and safety considerations, and the use and availability of reference materials for polymer identify verification. Utilising this information, a flowchart for applying FTIR spectroscopy to three-dimensional historic plastic objects during museum collection surveys is proposed to guide the conservation profession.

The effectiveness of three types of plastic bags used by the New South Wales Police Force for the storage of clandestine drug evidence has been investigated through a comparison of mechanical properties. The tensile and tear properties of “as received” low-density polyethylene (LDPE) and poly(vinyl chloride) (PVC) bags do not show major differences such that one type would be favoured over the other. However, the mechanical properties of the bags once exposed to a range of chemicals routinely collected as drug evidence have been shown to be influenced as a result of different chemical interactions. Although an interaction of reagents/solvents with an additive within the LDPE bags is proposed to influence the mechanical properties of the bags, the change in properties has been shown to be less severe than that observed for the PVC bag, where softening and damage of the bags results due to absorption of reagents.

We present a high-resolution neutron powder diffraction study of the triclinic β form of tripalmitin as well as in situ crystallisation experiments, monitored with neutron diffraction, conducted over three different cooling rates. We use the results from the high-resolution study to anticipate if neutron diffraction could be beneficial in differentiating the polymorphism in triacylglycerol systems. We extend on this to present analysis of a diffraction pattern of cocoa butter, to establish the potential for neutron diffraction to study the (hydrogenous) forms of triacylglycerols used in food production.

© 2018, © 2018 Australian Academy of Forensic Sciences. Plastics are one means of disposal of items or remains associated with criminal activity. The surface characteristics of plastic wrapping materials of forensic interest in soil environments have been investigated to determine the environmental factors that have the greatest influence on the degradation process of such polymers. Polyethylene bags and poly(vinyl chloride) sheeting were buried in model environments encompassing different soil types, moisture content, pH and temperature. Atomic force microscopy was used to monitor the changes to the polymer surface at a nanometre level. Over a two-year burial period, the degradation of polyethylene was found to be enhanced by an increased moisture content and an elevated soil pH. The plasticizer content of poly(vinyl chloride) was affected by burial and was observed to leach from the plastic in all environments continually over the burial period. A moist environment was shown to have a more pronounced effect on the removal of plasticizer. A measurement of the surface roughness of plastics using atomic force microscopy has been shown to be sensitive to the burial environment and demonstrates the potential of this technique to measure relatively subtle changes to burial items exposed to different environments.

© 2019, © 2019 Australian Academy of Forensic Sciences. The ability to monitor changes in human decomposition chemistry provides a potentially valuable tool for an understanding of the fate of human remains. This study reports the findings of an experimental study of a decomposing human cadaver investigated using infrared spectroscopy. This study was carried out at the Australian Facility for Taphonomic Experimental Research (AFTER) with a donated human cadaver clothed in cotton. An examination of the fluid retained by the cotton revealed that lipids and proteins, and their corresponding decomposition products, could be identified for the different stages of decomposition. The mechanisms for the changes to the lipid and protein components can be inferred from the spectroscopic changes observed and correlated with the corresponding decay processes observed for the cadaver. This study demonstrated that the use of this non-destructive technique allows the components of the decomposition fluid produced by decaying remains to be simultaneously monitored over time.

© 2019, © 2019 Australian Academy of Forensic Sciences. This project aimed to collect and analyze odour profiles from whole human cadavers across various seasons, to contribute to the understanding of the different volatile organic compounds (VOCs) produced in human decomposition. This research will ultimately enhance our understanding of the key VOCs used by cadaver-detection dogs to locate human remains. VOCs were collected onto sorbent tubes and analyzed using two-dimensional gas chromatography–time-of-flight-mass-spectrometry (GC×GC-TOFMS). Five trials were conducted at the Australian Facility for Taphonomic Experimental Research (AFTER) across various seasons including autumn, winter and spring. Analysis showed differentiation between compounds and compound classes produced by each donor. Cadavers placed during warmer weather showed higher variety and abundances of compounds and cadavers placed during cooler weather showed fewer VOCs with lower abundances. All seasonal trials showed variation, with no consistently recurring compound being identified. Further trials would need to be carried out in order to increase the VOC database, allowing for identification of key VOCs. This may consequently be used by cadaver-detection dogs for locating human remains at any time of the year.

© 2018 Elsevier B.V. A methodology to examine the human post-mortem decomposition process has been developed through the monitoring of chemical changes to decomposition fluids absorbed by clothing. Model surface burials using clothed pigs were established during summer and winter seasons in a temperate region of Australia. Three clothing materials were investigated: cotton, polyester and cotton-polyester. Lipid decomposition products were extracted from the textiles and the fatty acid composition measured as a function of burial time using gas chromatography – mass spectrometry (GC-MS). Two derivatisation methods for the fatty acids were compared to establish the most effective approach and it was established that a trimethylsilylation derivatisation method is the optimal preparation technique. The summer trials revealed two rates of transformation of fatty acids from unsaturated to saturated forms, with a faster rate of change occurring earlier in the trials. A different pattern of behaviour was observed for the fatty acids detected during the winter trial, with a decrease in saturated fatty acids initially observed, followed by the conversion of unsaturated to saturated fatty acids until the end of trial. The initial change observed during the winter trial was attributed to a dehydrogenation process caused by microbiological enyzymatic activity. The study has demonstrated the feasibility of examining lipid decomposition products collected in clothing from burials to provide insight into the conditions and length of burial.

© 2016 Elsevier Ireland Ltd. There is currently limited data available on the stabilities of the three stimulants 4-methylmethcathinone (4-MMC), 3,4-methylenedioxymethamphetamine (MDMA) and N-benzylpiperazine (BZP) in a putrefying matrix. A Gas Chromatography Mass Spectrometry (GC-MS) method to determine the concentration of the three drugs in putrefying porcine liver over a three month period was developed and validated. Both 4-MMC and BZP were found to be unstable, becoming undetectable and having an average recovery of 52% respectively after one month at ambient room temperature (20. °C). MDMA was found to be moderately stable, with an average recovery of 74% after three months at room temperature. This study indicated that the putrefaction process could have a significant impact on concentrations of 4-MMC and BZP in post-mortem cases involving putrefied remains.

Amongst the mid-20th century cultural objects from Papua New Guinea (PNG) in a collection of the Art Gallery of New South Wales (AGNSW), Australia, is a number of items that are coloured with an unusual blue pigment. Many of the paints used for the ceremonial objects originating from the PNG Highlands employ a traditional red, yellow, white and black palette, so there is interest in the source of a blue pigment of apparent natural origin. For this investigation, infrared and Raman spectroscopies, in combination with a synchrotron x-ray diffraction study, were used to characterise blue pigments obtained from three objects in the AGNSW collection. The pigments were identified as vivianite-type minerals. The different shades of blue appearing in these objects were found to be associated with an early oxidation product of vivianite, rather than due to the presence of another mineral in the paints.

© 2015, Springer-Verlag Berlin Heidelberg. An examination of the chemistry of adipocere formation in aquatic systems provides insight into how environmental factors affect the decomposition processes of human remains. Gas chromatography–mass spectrometry (GC-MS) and inductively coupled plasma–mass spectrometry (ICP-MS) have been employed to monitor the changes to the chemistry of adipocere formed in aquatic environments used to model seawater, river and chlorinated water systems. Seawater was shown to inhibit adipocere formation, and a distinctively different elemental composition was produced in this environment due to the high concentrations of salts. By comparison, river water has been shown to accelerate the formation of adipocere. Chlorinated water appears to significantly enhance adipocere formation, based on a comparison with established fatty acid concentration values. However, a competing reaction to form chlorohydrins in chlorinated water is believed to be responsible for the unusual findings in this environment. The application of the chemical characterisation of adipocere to an understanding of how this particular decomposition product forms in different water environments has been demonstrated, and there is potential to utilise this approach to identify the environment in which a body has been immersed.

© 2015, Springer Science+Business Media New York. Purpose: Cadaver-detection dogs use volatile organic compounds (VOCs) to search for human remains including those deposited on or beneath soil. Soil can act as a sink for VOCs, causing loading of decomposition VOCs in the soil following soft tissue decomposition. The objective of this study was to chemically profile decomposition VOCs from surface decomposition sites after remains were removed from their primary location. Methods: Pig carcasses were used as human analogues and were deposited on a soil surface to decompose for 3 months. The remains were then removed from each site and VOCs were collected from the soil for 7 months thereafter and analyzed by comprehensive two-dimensional gas chromatography–time-of-flight mass spectrometry (GC×GC–TOFMS). Results: Decomposition VOCs diminished within 6 weeks and hydrocarbons were the most persistent compound class. Decomposition VOCs could still be detected in the soil after 7 months using Principal Component Analysis. Conclusions: This study demonstrated that the decomposition VOC profile, while detectable by GC×GC–TOFMS in the soil, was considerably reduced and altered in composition upon removal of remains. Chemical reference data is provided by this study for future investigations of canine alert behavior in scenarios involving scattered or scavenged remains.

Essential to the success of proposed planetary Raman spectroscopy missions will be the preparation of comprehensive libraries of spectra and a greater understanding of the current limitations of Raman spectroscopy. Seven samples of Icelandic tephra were analysed using X-ray diffraction (XRD), Raman spectroscopy and Fourier transform infrared (FTIR) as an analogue for Martian rocks. The results from these three spectroscopic techniques were compared with the success of mineral identification of each method differing. Some minerals such as ilmenite and flouroapatite were identified using XRD and not found in the Raman spectra. Olivine, hematite and anatase were detected by Raman spectroscopy but were not observed in the XRD patterns. The FTIR results gave essential information on the presence of H2O in the samples. The impact of fluorescence on Raman spectra of some minerals is still a major concern as this is the most likely reason for some of the diagnostic mineral peaks not showing in the Raman spectra. Copyright © 2015 John Wiley & Sons, Ltd.

Increased characterisation of decomposition odour has improved existing knowledge regarding the decomposition volatile organic compound (VOC) profile of carrion. Validation of this dynamic decomposition VOC profile is required in order to characterise the variables that affect their production. This study was performed to determine whether the decomposition VOC profile produced under field conditions differed between summer and winter in an Australian environment. Outdoor studies were conducted using pig carcasses as human analogues in order to assess seasonal variation in the decomposition process. Common decomposition VOCs were identified using comprehensive two-dimensional gas chromatography – time of flight mass spectrometry (GC×GC-TOFMS). Fewer compounds and reduced abundance of VOCs was observed during winter. Relationships between the levels of detected decomposition VOCs and weather variables were established to be stronger in winter. Weak relationships during summer suggested the potential that an underlying variable (e.g. microbial activity, insect activity) had a stronger relationship to the abundance of decomposition VOCs. The seasonal robustness of the decomposition VOC profile is important to fields relying on the presence of a decomposition odour, i.e. search and recovery of victims in mass disasters, homicides, and missing persons cases.

This study demonstrates the first documented use of comprehensive two-dimensional gas chromatography – high-resolution time-of-flight mass spectrometry (GC×GC-HRTOFMS) for volatile organic compound analysis in the forensic sciences. High-resolution mass spectral data provided higher confidence in analyte identification. GC×GC-HRTOFMS will be valuable for future studies of decomposition odour and other complex volatile matrices.

Challenges in decomposition odour profiling have led to variation in the documented odour profile by different research groups worldwide. Background subtraction and use of controls are important considerations given the variation introduced by decomposition studies conducted in different geographical environments. The collection of volatile organic compounds (VOCs) from soil beneath decomposing remains is challenging due to the high levels of inherent soil VOCs, further confounded by the use of highly sensitive instrumentation. This study presents a method that provides suitable chromatographic resolution for profiling decomposition odour in soil by comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry using appropriate controls and field blanks. Logarithmic transformation and t-testing of compounds permitted the generation of a compound list of decomposition VOCs in soil. Principal component analysis demonstrated the improved discrimination between experimental and control soil, verifying the value of the data handling method. Data handling procedures have not been well documented in this field and standardisation would thereby reduce misidentification of VOCs present in the surrounding environment as decomposition byproducts. Uniformity of data handling and instrumental procedures will reduce analytical variation, increasing confidence in the future when investigating the effect of taphonomic variables on the decomposition VOC profile.

© 2017 Elsevier B.V. This paper presents a challenging case where organic materials in micro-sized paint samples extracted from mid-20th century ceremonial objects of the Papua New Guinea (PNG) Highlands are characterized using FTIR microscopy, with the aid of solvent extraction and pre-treatment with hydrofluoric acid (HF) targeted for micro-sized samples, as well as Raman microscopy and SEM-EDS. An eclectic range of binder classes including plant-based organic matter, animal fat, wax, natural and synthetic resin, were identified on several ceremonial objects based on spectral signatures. The tree resins detected (tigaso oil and kilt tree resin) are specific to the natural flora from the PNG Highlands. Tannin-rich charred wood forming the base substrate of different ceremonial objects was also identified. In addition, degradation products from metal soaps from both synthetic and biological sources were identified.

A truly interdisciplinary approach to this core subject within Forensic Science Combines essential theory with practical crime scene work Includes case studies Applicable to all time periods so has relevance for conventional archaeology, ...

© 2017 The Author(s). The many thousands of Aboriginal rock art sites extending across Australia represent an important cultural record. The styles and materials used to produce such art are of great interest to archaeologists and those concerned with the protection of these significant works. Through an analysis of the mineral pigments utilised in Australian rock art, insight into the age of paintings and practices employed by artists can be gained. In recent years, there has been an expansion in the use of modern analytical techniques to investigate rock art pigments and this paper provides a review of the application of such techniques to Australian sites. The types of archaeological information that may be extracted via chemical analysis of specimens collected from or at rock art sites across the country are discussed. A review of the applicability of the techniques used for elemental analysis and structural characterisation of rock art pigments is provided and how future technological developments will influence the discipline is investigated.

© 2017 Elsevier B.V. Textiles are a valuable source of forensic evidence and the nature and condition of textiles collected from a crime scene can assist investigators in determining the nature of the death and aid in the identification of the victim. Until now, much of the knowledge of textile degradation in forensic contexts has been based on the visual inspection of material collected from soil environments. The purpose of the current study was to investigate the potential of a more quantitative approach to the understanding of forensic textile degradation through the application of infrared spectroscopy. Degradation patterns of natural and synthetic textile materials as they were subjected to a natural outdoor environment in Australia were investigated. Cotton, polyester and polyester – cotton blend textiles were placed on a soil surface during the summer and winter seasons and were analysed over periods 1 and 1.5 years, respectively, and examined using attenuated total reflectance (ATR) spectroscopy. Statistical analysis of the spectral data obtained for the cotton material correlated with visual degradation and a difference in the onset of degradation between the summer and winter season was revealed. The synthetic material did not show any signs of degradation either visually or statistically throughout the experimental period and highlighted the importance of material type in terms of preservation. The cotton section from the polyester – cotton blend samples was found to behave in a similar manner to that of the 100% cotton samples, however principal component analysis (PCA) demonstrated that the degradation patterns were less distinct in both the summer and winter trial for the blend samples. These findings indicated that the presence of the synthetic material may have inhibited the degradation of the natural material. The use of statistics to analyse the spectral data obtained for textiles of forensic interest provides a better foundation for the interpretation of the data obtained using ATR-FTIR spectroscopy, and has provided insight into textile degradation processes relevant to a soil environment.

A truly interdisciplinary approach to this core subject within Forensic Science Combines essential theory with practical crime scene work Includes case studies Applicable to all time periods so has relevance for conventional archaeology, ...

© 2017 Elsevier B.V. During the second-third century, cremation was progressively abandoned for inhumation in the Roman Empire and was accompanied by new funeral practices. Recent archaeological excavations in the catacombs of Saints Peter and Marcellinus in Rome revealed thousands of formerly undiscovered skeletons of individuals plastered and methodically stacked in previously unknown and inaccessible rooms. By setting up and applying a multi-analytical approach to characterize chemically all amorphous materials surrounding the skeletons, we investigated this important cultural change regarding the treatment of death. Chemical characterization of the amorphous samples was achieved using FTIR spectroscopy and gas chromatography/mass spectrometry (Py-GC/MS and GC/MS) and by comparison with reference samples from known origin. This allowed for the unambiguous identification of precious and exotic resinous substances involved in the embalming process of the bodies. Amber, sandarac and frankincense, which were sourced from widespread locations, were used as part of the funerary treatment. This first evidence of such highly prized commodities in burial process provides us with new insight into funerary practices as well as commercial networks in the Roman Empire during the first centuries A.D.

An investigation of the curing (polymerisation) rate of acrylamide was carried out using isothermal and non-isothermal DSC in order to estimate the time for complete conversion of monomer at ambient temperatures. The non-isothermal data were used to model the rate using integral isoconversional and incremental isoconversional kinetic methods. Applying the equations for integral isoconversional methods and extrapolating to ambient temperatures resulted in non-sensical conversion-time curves, where the time estimated decreased for increasing degree of conversion to be reached. This odd behaviour was attributed to the incorrectness of the integration where the kinetic parameters (e.g. The activation energy) are a function of conversion. The problem was addressed by applying incremental methods which provided more reasonable results as the integration is carried out over small conversion increments where the kinetic parameters are assumed to be constant. Estimates of the conversion were compared to isothermal measurements and, although isothermal DSC produced significant variability in the data, extrapolated estimates from non-isothermal kinetic analysis produced, at best, an upper boundary for the estimation of the time to reach a fixed degree of conversion. © 2014 Akadémiai Kiadó, Budapest, Hungary.

© 2017 Elsevier B.V. In the area of clandestine laboratory investigations, plastic bags are used to collect and store evidence, such as solvents, precursors, and other compounds usually employed for the manufacturing of drugs (although liquids may be stored in glass containers within the bags first). In this study, three different types of plastic bags were provided by the NSW Police Force and investigated for their suitability for evidence collection: two different types of low-density polyethylene (LDPE) bags and one type of polyvinyl chloride (PVC) bag. Three different experiments were carried out: (1) storing relevant chemicals in the bags for up to three months; (2) exposing the bags including their content to accelerated conditions using a weatherometer, and (3) simulating an expected real case scenario. This study indicates that drugs and related chemicals stored in plastic bags may lead to a change in the composition of the chemical and an alteration or degradation of the plastic bag. All experiments led to the same conclusion: the polyvinyl chloride bags appeared to be the most affected. LDPE bags seem to be more appropriate for routine use, although it has been established they are not suitable for the collection of liquids (unless pre-packaged in, for instance, a glass container).

International audience; The chemistry of pigments used to create rock art at a rock shelter in northern Australia has characterised so as to gain a better understanding of the origins of the colours used. The site, Dalakngalarr 1, located in Jawoyn Country in Arnhem Land contains hundreds of paintings in various colours and styles. Striking and well-preserved X-ray images were painted across the site using ochre pigments that contain an iron oxide colourant mixed with clay to produce yellow, red and a distinctive purple colour. Infrared and Raman microscopy were used to confirm that the yellow pigment colouration is due to the presence of goethite. Both the red and purple pigments were shown to contain haematite, but there are microstructural differences between the two that account for the differences in the observed colour. Optical microscopy and scanning electron microscopy also demonstrate differences in the morphologies of the red and purple pigments. The purple pigment was found to a have a pure haematite structure, which is proposed to result from heating of the pigment source. Keywords: Rock art; Ochre; Haematite; Raman microscopy; infrared microspectroscopy; Scanning electron microscopy

Plastic materials are a source of items that may be located in clandestine grave sites. Knowledge of their type and state of preservation or deterioration may provide a valuable resource for the identification of a victim or perpetrator. This study involves an examination of the effect of the nature of the soil environment on the structural properties of two common polymers, poly(vinyl chloride) and nylon, over a period of 18 months. These polymers represent common types of plastic sheeting and carpet material that may be used to wrap a body. Infrared spectroscopy and scanning electron microscopy have been used to monitor the structural changes that occur to these polymers in a soil environment and degradation mechanisms are proposed.

© 2015 Elsevier B.V. Fifty ceremonial objects collected between 1961 and 1972 from various parts of the Papua New Guinea (PNG) Highlands and later acquired into the Art Gallery of New South Wales, Australia were analysed using Raman and Fourier-Transform Infrared (FTIR) spectroscopy coupled with microscopy and in some instances, complemented with scanning electron microscopy-Energy dispersive spectroscopy (SEM-EDS) and X-ray diffraction (XRD). Both synthetic and natural pigments were identified and correlated to the source of the objects collected. The distribution of synthetic pigments in Highlands artefacts was found to be widespread, of which PR3, PY1 and ultramarine blues dominated the synthetic palette. Rare blue vivianites were detected on objects collected in the Wiru and Kewa speaking regions of the Southern Highlands, in addition to the more widespread iron oxide-hydroxide pigments, such as limonite, goethite, lepidocrocite and hematite, as well as kaolinite. The results of the study rectified about 30% of the material documentation, which had previously misidentified pigments based on qualitative and anecdotal interpretation.

Infrared spectroscopy has been used to examine changes to bone chemistry as a result of soil burial. Pig carcasses were buried as part of a controlled field study, and pig bone was used in soil environments established in the laboratory. The variables of species type, bone pretreatment, soil type and pH, moisture content, temperature, and burial time were investigated. The crystallinity index (CI) and the organic and carbonate contents of the bones were monitored. The data revealed decreasing trends in the organic and carbonate contents and an increase in the CI of the bone with burial time. An acidic soil environment and soil type are the factors that have the most influence on bone chemistry as a result of burial. The study demonstrates the potential of infrared spectroscopy as a straightforward method of monitoring the changes associated with aging of bones in a variety of soil environments. © 2012 American Academy of Forensic Sciences.

Adipocere is a postmortem decomposition product that consists of a mixture of fatty acids. The rate of formation of adipocere from pig adipose tissue in an aqueous environment has been monitored. The effect of various clothing and carpet material types on the process was investigated. The fatty acid composition of the adipocere was determined at regular intervals using gas chromatography–mass spectrometry. Examination of the changes to fatty acid concentrations allowed the degree of adipocere formation in the different environments to be estimated. The study demonstrated that the rate at which adipocere forms is particularly accelerated by the presence of coverings produced from natural materials. Elemental analysis by inductively coupled plasma–mass spectrometry revealed, for the most part, little change to the cations present in the adipocere formed. However, an increase in Ca concentration was observed for tissue wrapped in acrylic carpet, which was associated with a CaCO3 additive used in the carpet manufacture.

The degradation of Sydney sandstone used to build the heritage St Mary's Cathedral in Sydney, Australia, has been investigated using environmental scanning electron microscopy combined with energy dispersive X-ray spectroscopy. This technique provided the structural details of the cementing clay and an elemental characterization the sandstone. The observed differences in the elemental composition of the unweathered and weathered sandstones were associated with changes to the clay microstructure upon weathering. The results support the substitution theory that Fe3+ replaces Al3+ in the kaolinite clay component upon weathering. An examination of the impurities present prior to a nonstructural iron removal treatment revealed the presence of minerals that may provide a source of the elements responsible for the substitution process.

The tensile and tear properties of a biodegradable polymer, Biomax®, have been studied in order to assess this material in film applications. While the tensile strength of Biomax® was comparable to that of low-density polyethylene, the tear strength was found to be six times lower. A study of the load-displacement curves revealed a regular variation in load throughout the test, which was attributed to the presence of lower and higher strength regions in the polymer. The higher strength regions were characterized by the presence of polymer chains oriented parallel to the tear surface, while the lower strength regions were defined by an absence of molecular orientation and the presence of voids. Copyright © Taylor & Francis Group, LLC.

Thermal analysis has been employed in a study of the degradation of heritage Sydney sandstone used in St Mary's Cathedral in Sydney, Australia. TG and DSC have been used to characterise the clay components removed from weathered and unweathered sandstone. Two types of kaolin clays - kaolinite and its polymorph, dickite - have been identified. A higher amount of dickite present in the clay of weathered sandstone indicates that a kaolinite-to-dickite transformation occurs upon weathering. XRD hot stage analysis was also used to demonstrate the presence of a more thermally stable polymorph of the kaolinite. © 2008 Springer Science+Business Media, LLC.

A challenge for forensic examiners is the ageing and characterisation of bone fragments or decomposed skeletal remains. Due to the sensitivity of thermal methods to morphological states, thermal analysis has been selected as a technique which could overcome the difficulties. In this preliminary study, TG-MS was applied to the characterisation of bone fragments derived from the compact bone of pig rib specimens. TG-MS curves were collected by heating bone samples to 1000°C in an argon atmosphere. Under these conditions, both the organic and inorganic phases decomposed, producing a variety of organic fragments and carbon dioxide. Pyrolysis of the organic phase, which is composed predominantly of collagen, occurred resulting in the observation of ion fragments up to 110 amu. Selected fragments were monitored and their observation is discussed in terms of the decomposition of both the collagen phase and the inorganic carbonated hydroxyapatite phase. © Springer-Verlag 2007.

Aminated poly(ethylene terephthalate) (PET) surfaces were characterized for their use as substrates for the attachment of biologically active molecules. Amines of different chain lengths, tetraethylenepentamine, triethylenetetraamine (TTETA), and diethylenetriamine (DETA), were investigated. X-ray photoelectron spectroscopy was used to show that each amine introduced a comparable amount of nitrogen (5 atom %) to the PET surface. Contact-angle and titration analyses indicated that the amination reaction was not restricted to the surface, with evidence of diffusion into the polymer by TTETA and DETA. As a result, degradation of the PET substrate, evidenced by mass loss, was observed to occur. Annealing of the PET films before amination at a temperature of 200°C reduced the extent of degradation without producing a decrease in the nitrogen content produced. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008

© 2016 Elsevier B.V.. A novel microfluidic paper-based analytical device (μPAD) was designed to filter, extract, and pre-concentrate explosives from soil for direct analysis by a lab on a chip (LOC) device. The explosives were extracted via immersion of wax-printed μPADs directly into methanol soil suspensions for 10 min, whereby dissolved explosives travelled upwards into the μPAD circular sampling reservoir. A chad was punched from the sampling reservoir and inserted into a LOC well containing the separation buffer for direct analysis, avoiding any further extraction step. Eight target explosives were separated and identified by fluorescence quenching. The minimum detectable amounts for all eight explosives were between 1.4 and 5.6 ng with recoveries ranging from 53-82% from the paper chad, and 12-40% from soil. This method provides a robust and simple extraction method for rapid identification of explosives in complex soil samples.

© 2015 Elsevier Ireland Ltd. Textiles are a commonly encountered source of evidence in forensic cases. In the past, most research has been focused on how textiles affect the decomposition process while little attention has been paid to how the decomposition products interact with the textiles. While some studies have shown that the presence of remains will have an effect on the degradation of clothing associated with a decaying body, very little work has been carried out on the specific mechanisms that prevent or delay textile degradation when in contact with decomposing remains. In order to investigate the effect of decomposition fluid on textile degradation, three clothed domestic pig (. Sus scrofa domesticus) carcasses were placed on a soil surface, textile specimens were collected over a period of a year and were then analysed using ATR-FTIR spectroscopy and GC-MS. Multivariate statistical analysis was used to analyse the data. Cotton specimens not associated with remains degraded markedly, whereas the samples exposed to decomposition fluids remained relatively intact over the same time frame. An investigation of the decomposition by-products found that the protein-related bands remained stable and unchanged throughout the experiment. Lipid components, on the other hand, demonstrated a significant change this was confirmed with the use of both ATR-FTIR spectroscopy and GC-MS. Through an advanced statistical approach, information about the decomposition by-products and their characteristics was obtained. There is potential that the lipid profile in a textile specimen could be a valuable tool used in the examination of clothing located at a crime scene.