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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.forsciint.2009.07.013 Byline: Cedric Neumann (a)(b), Pierre Margot (a) Keywords: Ink examination; Comparison; Identification; Interpretation; Likelihood ratio Abstract: The research reported in this series of article aimed at (1) automating the search of questioned ink specimens in ink reference collections and (2) at evaluating the strength of ink evidence in a transparent and balanced manner. These aims require that ink samples are analysed in an accurate and reproducible way and that they are compared in an objective and automated way. This latter requirement is due to the large number of comparisons that are necessary in both scenarios. A research programme was designed to (a) develop a standard methodology for analysing ink samples in a reproducible way, (b) comparing automatically and objectively ink samples and (c) evaluate the proposed methodology in forensic contexts. This report focuses on the last of the three stages of the research programme. The calibration and acquisition process and the mathematical comparison algorithms were described in previous papers [C. Neumann, P. Margot, New perspectives in the use of ink evidence in forensic science -- Part I: Development of a quality assurance process for forensic ink analysis by HPTLC, Forensic Sci. Int. 185 (2009) 29-37; C. Neumann, P. Margot, New perspectives in the use of ink evidence in forensic science -- Part II: Development and testing of mathematical algorithms for the automatic comparison of ink samples analysed by HPTLC, Forensic Sci. Int. 185 (2009) 38-50]. In this paper, the benefits and challenges of the proposed concepts are tested in two forensic contexts: (1) ink identification and (2) ink evidential value assessment. The results show that different algorithms are better suited for different tasks. This research shows that it is possible to build digital ink libraries using the most commonly used ink analytical technique, i.e. high-performance thin layer chromatography, despite its reputation of lacking reproducibility. More importantly, it is possible to assign evidential value to ink evidence in a transparent way using a probabilistic model. It is therefore possible to move away from the traditional subjective approach, which is entirely based on experts' opinion, and which is usually not very informative. While there is room for the improvement, this report demonstrates the significant gains obtained over the traditional subjective approach for the search of ink specimens in ink databases, and the interpretation of their evidential value. Author Affiliation: (a) School of Forensic Science, University of Lausanne, CH-1015 Dorigny, Switzerland (b) The Forensic Science Service Ltd., 2920 Trident Court, Birmingham B37 7YN, United Kingdom Article History: Received 14 April 2009; Revised 16 June 2009; Accepted 17 July 2009

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.forsciint.2009.06.005 Byline: Andy Becue, Sebastien Moret, Christophe Champod, Pierre Margot Keywords: Detection; Latent fingermarks; Blood; Nanoparticles; Quantum dots; Luminescence; Acid Yellow 7 Abstract: A new and original reagent based on the use of highly fluorescent cadmium telluride (CdTe) quantum dots (QDs) in aqueous solution is proposed to detect weak fingermarks in blood on non-porous surfaces. To assess the efficiency of this approach, comparisons were performed with one of the most efficient blood reagents on non-porous surfaces, Acid Yellow 7 (AY7). To this end, four non-porous surfaces were studied, i.e. glass, transparent polypropylene, black polyethylene, and aluminium foil. To evaluate the sensitivity of both reagents, sets of depleted fingermarks were prepared, using the same finger, initially soaked with blood, which was then successively applied on the same surface without recharging it with blood or latent secretions. The successive marks were then cut in halves and the halves treated separately with each reagent. The results showed that QDs were equally efficient to AY7 on glass, polyethylene and polypropylene surfaces, and were superior to AY7 on aluminium. The use of QDs in new, sensitive and highly efficient latent and blood mark detection techniques appears highly promising. Health and safety issues related to the use of cadmium are also discussed. It is suggested that applying QDs in aqueous solution (and not as a dry dusting powder) considerably lowers the toxicity risks. Author Affiliation: Institut de Police Scientifique, School of Criminal Sciences, Batochime, University of Lausanne, CH-1015 Lausanne, Switzerland Article History: Received 30 March 2009; Revised 29 May 2009; Accepted 5 June 2009

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.forsciint.2009.03.015 Byline: Ines Baer, Pierre Margot Keywords: Ecstasy; Fatty acids; Bortrifluoride; FAME; Liquid-liquid extraction; GC-MS Abstract: Fatty acids are the basis of so-called stearates which are frequently used as lubricants in the production of ecstasy tablets. Being a product added at the initial tablet production step its composition does not change once the compression is performed. The analysis of fatty acids can therefore provide useful information for a drug intelligence purpose. In this context an appropriate analytical method was developed to improve results already obtained by routine analyses. Considering the small quantity of such fatty acids in ecstasy tablets ([approximately equal to]3%) the research focussed on their extraction and concentration. Two different procedures were tested: (1) liquid/liquid extraction using dichloromethane followed by derivatisation and (2) in situ transesterification using bortrifluoride. Analyses were performed by GC-MS. The two procedures were optimized and applied to eight ecstasy seizures, in order to choose one of the procedures for its application to a large ecstasy sample set. They were compared by considering the number of peaks detected and sample amount needed, reproducibility and other technical aspects. Author Affiliation: Institut de Police Scientifique, University of Lausanne, BCH, 1015 Lausanne-Dorigny, Switzerland Article History: Received 26 May 2008; Revised 14 December 2008; Accepted 17 March 2009

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.forsciint.2009.03.004 Byline: Federica Bonadio, Pierre Margot, Olivier Delemont, Pierre Esseiva Keywords: Drug profiling; HS-SPME; Ecstasy; Data treatment Abstract: A headspace solid-phase microextraction procedure (HS-SPME) was developed for the profiling of traces present in 3,4-methylenedioxymethylampethamine (MDMA). Traces were first extracted using HS-SPME and then analyzed by gas chromatography-mass spectroscopy (GC-MS). The HS-SPME conditions were optimized using varying conditions. Optimal results were obtained when 40mg of crushed MDMA sample was heated at 80 [degrees]C for 15min, followed by extraction at 80 [degrees]C for 15min with a polydimethylsiloxane/divinylbenzene coated fibre. A total of 31 compounds were identified as traces related to MDMA synthesis, namely precursors, intermediates or by-products. In addition some fatty acids used as tabletting materials and caffeine used as adulterant, were also detected. The use of a restricted set of 10 target compounds was also proposed for developing a screening tool for clustering samples having close profile. 114 seizures were analyzed using an SPME auto-sampler (MultiPurpose Samples MPS2), purchased from Gerstel GMBH & Co. (Germany), and coupled to GC-MS. The data was handled using various pre-treatment methods, followed by the study of similarities between sample pairs based on the Pearson correlation. The results show that HS-SPME, coupled with the suitable statistical method is a powerful tool for distinguishing specimens coming from the same seizure and specimens coming from different seizures. This information can be used by law enforcement personnel to visualize the ecstasy distribution network as well as the clandestine tablet manufacturing. Author Affiliation: Ecole des Sciences Criminelles, Institut de Police Scientifique, University of Lausanne, Batochime, CH-1015, Lausanne-Dorigny, Switzerland Article History: Received 14 September 2008; Revised 9 January 2009; Accepted 2 March 2009

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.forsciint.2008.11.017 Byline: Valerie Drapel, Andy Becue, Christophe Champod, Pierre Margot Keywords: Fingerprints; Antibodies; Stratum corneum; Eccrine sweat; Keratin; Cathepsin-D; Dermcidin Abstract: An analysis of latent fingermark residues by Sodium-Dodecyl-Sulfate PolyAcrylamide Gel Electrophoresis (SDS-PAGE) followed by silver staining allowed the detection of different proteins, from which two major bands, corresponding to proteins of 56 and 64kDa molecular weight, could be identified. Two other bands, corresponding to proteins of 52 and 48kDa were also visualizable along with some other weaker bands of lower molecular weights. In order to identify these proteins, three antibodies directed against human proteins were tested on western blots of fingermarks residues: anti-keratin 1 and 10 (K1/10), anti-cathepsin-D (Cat.D) and anti-dermcidin (Derm.). The corresponding antigens are known to be present in the stratum corneum of desquamating stratified epithelium (K1/10, Cat.D) and/or in eccrine sweat (Cat.D, Derm.). The two major bands were identified as consistent with keratin 1 and 10. The pro-form and the active form of the cathepsin-D have also been identified from two other bands. Dermcidin could not be detected in the western blot. In addition, these antibodies have been tested on latent fingermarks left on polyvinylidene fluoride (PVDF) membrane, as well as on whitened and non-whitened paper. The detection of fingermarks was successful with all three antibodies. Author Affiliation: University of Lausanne-ESC, Lausanne, Switzerland Article History: Received 19 June 2008; Revised 3 November 2008; Accepted 29 November 2008

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.forsciint.2008.04.008 Byline: Andy Becue, Aurele Scoundrianos, Christophe Champod, Pierre Margot Keywords: Fingermark detection; Non-porous surfaces; Multimetal deposition; Luminescence; Metal nanoparticles; Gold; Zinc oxide Abstract: The in situ deposition of zinc oxide on gold nanoparticles in aqueous solution has been here successfully applied in the field of fingermark detection on various non-porous surfaces. In this article, we present the improvement of the multimetal deposition, an existing technique limited up to now to non-luminescent results, by obtaining luminescent fingermarks with very good contrast and details. This is seen as a major improvement in the field in terms of selectivity and sensitivity of detection, especially on black surfaces. Author Affiliation: Institut de Police Scientifique, School of Criminal Sciences, Batochime, University of Lausanne, CH-1015 Lausanne, Switzerland Article History: Received 5 March 2008; Accepted 12 April 2008

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.forsciint.2007.12.008 Byline: S. Lociciro (a), P. Esseiva (a), P. Hayoz (a), L. Dujourdy (b), F. Besacier (b), P. Margot (a) Keywords: Cocaine; Drug profiling; Inter-laboratory comparison; ROC curve; Pre-treatments; Cosine and Pearson correlation; Statistics Abstract: Harmonisation and optimization of analytical and statistical methodologies were carried out between two forensic laboratories (Lausanne, Switzerland and Lyon, France) in order to provide drug intelligence for cross-border cocaine seizures. Part I dealt with the optimization of the analytical method and its robustness. This second part investigates statistical methodologies that will provide reliable comparison of cocaine seizures analysed on two different gas chromatographs interfaced with a flame ionisation detectors (GC-FIDs) in two distinct laboratories. Sixty-six statistical combinations (ten data pre-treatments followed by six different distance measurements and correlation coefficients) were applied. One pre-treatment (N+S: area of each peak is divided by its standard deviation calculated from the whole data set) followed by the Cosine or Pearson correlation coefficients were found to be the best statistical compromise for optimal discrimination of linked and non-linked samples. The centralisation of the analyses in one single laboratory is not a required condition anymore to compare samples seized in different countries. This allows collaboration, but also, jurisdictional control over data. Author Affiliation: (a) Institut de Police Scientifique, Ecole des Sciences Criminelles, Universite de Lausanne, BCH, 1015 Lausanne-Dorigny, Switzerland (b) Laboratoire de Police Scientifique de Lyon, 31 avenue Franklin Roosevelt, 69134 Ecully Cedex, France Article History: Received 27 September 2007; Revised 5 December 2007; Accepted 21 December 2007

There is a serious issue within the forensic science community, which even extends outside of the field. The role of the scientist in the investigation of crime has been increasingly confined to the laboratory, which has been accompanied by the conflation of the terms forensic science and criminalistics. This unfortunate situation has been festering for years. To make matters worse, the era of the proactive, problem‐defining, criminalist (generalist) is waning, and possibly over. Present‐day "criminalists" are treated as little more than reactive, protocol‐constrained, laboratory technicians, with few, if any, consequential crime scene roles. In most cases, these "criminalists" merely respond to routine requests from prosecutors and police. The absence of science at the front end of forensic investigations, i.e., the scene, has resulted in biased, ineffective, inefficient, and/or erroneous outcomes with immediate and long‐term societal impacts. To disentangle this imbroglio, we propose the use of another term, traceology, which has seen limited use worldwide except in the field of archaeology. With respect to criminalistics, this term has been previously proposed by Margot (20–21). Traceology is an historical science, dealing with the examination, analysis, and scientific interpretation of event traces (signs or remnants) of earlier activities. In this commentary, we define and redefine familiar, but ambiguous, terms and concepts with the hope of recapturing the essence of criminalistics (32), which we suggest is best termed traceology. [ABSTRACT FROM AUTHOR]