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1.
Forensic Sci Int ; 324: 110848, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34111809

RESUMEN

Illicit drug profiling (i.e. chemical and/or physical profiling) to compare and relate illicit drugs samples has been actively used in routine case work at the National Bureau of Investigation (NBI) in Finland. This preliminary and exploratory work reviews NBI's illicit drug profiling practices. Particular emphasis is put on communication of forensic results and how the NBI has promoted the use of forensic data in an intelligence perspective by establishing a case coordination service. Moreover, our study evaluates the comprehension, integration and usefulness of illicit drug profiling from end users' point of view by means of an online survey and face-to-face interviews. Findings are compared with theoretical aspects as described in literature. Results show that in the Finnish context illicit drug profiling is used and useful in the investigation and in court. From end users' perspective, real practical relevance relies in its use as intelligence during the investigation. However, to be truly useful, illicit drug profiling results must be communicated promptly during the investigation, with sufficient clarity and interpreted correctly by end users. Factors influencing the integration of illicit drug profiling in the forensic process are addressed.


Asunto(s)
Tráfico de Drogas , Toxicología Forense , Drogas Ilícitas/química , Finlandia , Humanos , Aplicación de la Ley
2.
Oecologia ; 182(4): 1083-1093, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27665542

RESUMEN

The alternative prey hypothesis (APH) states that when the density of the main prey declines, generalist predators switch to alternative prey and vice versa, meaning that predation pressure on the alternative prey should be negatively correlated with the density of the main prey. We tested the APH in a system comprising one generalist predator (pine marten, Martes martes), cyclic main prey (microtine voles, Microtus agrestis and Myodes glareolus) and alternative prey (cavity nests of common goldeneye, Bucephala clangula); pine marten is an important predator of both voles and common goldeneye nests. Specifically, we studied whether annual predation rate of real common goldeneye nests and experimental nests is negatively associated with fluctuation in the density of voles in four study areas in southern Finland in 2000-2011. Both vole density and nest predation rate varied considerably between years in all study areas. However, we did not find support for the hypothesis that vole dynamics indirectly affects predation rate of cavity nests in the way predicted by the APH. On the contrary, the probability of predation increased with vole spring abundance for both real and experimental nests. Furthermore, a crash in vole abundance from previous autumn to spring did not increase the probability of predation of real nests, although it increased that of experimental nests. We suggest that learned predation by pine marten individuals, coupled with efficient search image for cavities, overrides possible indirect positive effects of high vole density on the alternative prey in our study system.


Asunto(s)
Arvicolinae , Dinámica Poblacional , Animales , Mustelidae , Conducta Predatoria , Estaciones del Año
3.
Forensic Sci Int ; 169(1): 86-99, 2007 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-17182203

RESUMEN

Amphetamine samples were analysed by gas chromatography-mass spectrometry (GC-MS), and the peak areas of 33 target compounds were transformed by applying various pretreatment techniques. The objective was to optimise the ability of a number of distance metrics to establish links between samples of amphetamine originating from the same batch (henceforth referred to as linked distances). Furthermore, partial least squares discriminant analysis (PLS-DA) was used to evaluate the effects of various pretreatment methods on separation of amphetamine batches synthesised by the Leuckart reaction, reductive amination of benzyl methyl ketone, and the nitrostyrene route. The most efficient way to pretreat GC-MS data varied for the different distance metrics, although best results were obtained when data were normalised to the sum of peak areas, and either the fourth root or a logarithm was applied to the normalised data. When pretreating normalised data by fourth root transformation, Pearson correlation was the distance metric that was most successful at finding linked samples. Normalisation and the use of fourth root also represented the best method of pretreating data when employing PLS-DA to separate samples synthesised by different routes. To achieve a faster and more user-friendly procedure for evaluating chromatograms, experiments were performed in which the number of target compounds used to compare samples was reduced. The effect of each compound that was removed was studied by applying PLS-DA and by using Pearson correlation to calculate linked distances as well as unlinked distances (between samples from different batches of amphetamine). Considering both links between samples from the same batch and separation of samples synthesised by different routes, the best results were obtained with the data set comprising 26 compounds. Finally, it was found that the profiling method developed in this work was superior to an existing technique with respect to separating linked and unlinked distances.

4.
Forensic Sci Int ; 169(1): 77-85, 2007 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-17178203

RESUMEN

This paper is the fifth in a series of six in relation to the development of a harmonised method for the profiling of amphetamine [L. Aalberg, K. Andersson, C. Bertler, H. Borén, M.D. Cole, J. Dahlén, Y. Finnon, H. Huizer, K. Jalava, E. Kaa, E. Lock, A. Lopes, A. Poortman-van der Meer, E. Sippola, Development of a harmonised method for the profiling of amphetamines I. Synthesis of standards and compilation of analytical data, Forensic Sci. Int. 149 (2005) 219-229; L. Aalberg, K. Andersson, C. Bertler, M.D. Cole, Y. Finnon, H. Huizer, K. Jalava, E. Kaa, E. Lock, A. Lopes, A. Poortman-van der Meer, E. Sippola, J. Dahlén, Development of a harmonised method for the profiling of amphetamines II. Stability of impurities in organic solvents, Forensic Sci. Int. 149 (2005) 231-241]. The third paper [K. Andersson, K. Jalava, E. Lock, L. Aalberg, Y. Finnon, H. Huizer, E. Kaa, A. Lopes, A. Poortman-van der Meer, M.D. Cole, J. Dahlén, E. Sippola, Development of a harmonised method for the profiling of amphetamines III. Development of the gas chromatographic method, Forensic Sci. Int., in press] dealt with the optimisation of the gas chromatographic and detection methods whereas the fourth paper [K. Andersson, K. Jalava, E. Lock, Y. Finnon, S. Stevenson, L. Aalberg, H. Huizer, E. Kaa, A. Lopes, A. Poortman-van der Meer, M.D. Cole, J. Dahlén, E. Sippola, Development of a harmonised method for the profiling of amphetamines IV. Optimisation of sample preparation, Forensic Sci. Int., in press] concerned the optimisation of the extraction method prior to GC analysis. This paper is a study of the optimised method in order to determine its stability. Investigations of within and between day variations were carried out in four laboratories. Moreover, variations between laboratories were also determined. Both flame ionisation detector (FID) and MS detection were used. One laboratory studied nitrogen-phosphorous detector (NPD) detection as well. For this task, 12 batches of amphetamine were prepared. Six of them were synthesised via the Leuckart route, three via the nitrostyrene route and three via the reductive amination route [A.M.A. Verweij, Impurities in illicit drug preparations: amphetamine and methamphetamine, Forensic Sci. Rev. 1 (1989) 2-11]. Taking into account all studied target compounds and the average results from four laboratories, the within day variation was around 6% for FID and 5% for MS, the between days variation was around 10% for FID and 8% for MS. For NPD detection, within day variation was 5% and between days variation 9% (only one laboratory). Finally, the inter-laboratory variation was about 12% for FID (four laboratories) and 10% for MS (three laboratories).

5.
Forensic Sci Int ; 169(1): 64-76, 2007 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-17134863

RESUMEN

The suitability of liquid-liquid extraction (LLE) and solid-phase extraction (SPE) for the preparation of impurity extracts intended for gas chromatographic profiling analyses of amphetamine were evaluated. Both techniques were optimised with respect to the extraction of selected target compounds by use of full factorial designs in which the variables affecting the performance were evaluated. Test samples consisted of amphetamine synthesised by the Leuckart reaction, by reductive amination of benzyl methyl ketone and by the nitrostyrene route. The performance of LLE and SPE were comparable in terms of repeatability and recovery of the target compounds. LLE was considered the better choice for the present harmonised amphetamine profiling method due to the lack of information on the long-term stability of SPE columns.

6.
Forensic Sci Int ; 169(1): 50-63, 2007 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-17174497

RESUMEN

This study focused on gas chromatographic analysis of target compounds found in illicit amphetamine synthesised by the Leuckart reaction, reductive amination of benzyl methyl ketone, and the nitrostyrene route. The analytical method was investigated and optimised with respect to introduction of amphetamine samples into the gas chromatograph and separation and detection of the target substances. Sample introduction using split and splitless injection was tested at different injector temperatures, and their ability to transfer the target compounds to the GC column was evaluated using cold on column injection as a reference. Taking the results from both techniques into consideration a temperature of 250 degrees C was considered to be the best compromise. The most efficient separation was achieved with a DB-35MS capillary column (35% diphenyl 65% dimethyl silicone; 30 m x 0.25 mm, d(f) 0.25 microm) and an oven temperature program that started at 90 degrees C (1 min) and was increased by 8 degrees C/min to 300 degrees C (10 min). Reproducibility, repeatability, linearity, and limits of determination for the flame ionisation detector (FID), nitrogen phosphorous detector (NPD), and mass spectrometry (MS) in scan mode and selected ion monitoring (SIM) mode were evaluated. In addition, selectivity was studied applying FID and MS in both scan and SIM mode. It was found that reproducibility, repeatability, and limits of determination were similar for FID, NPD, and MS in scan mode. Moreover, the linearity was better when applying FID or NPD whereas the selectivity was better when utilising the MS. Finally, the introduction of target compounds to the GC column when applying injection volumes of 0.2 microl, 1 microl, 2 microl, and 4 microl with splitless injection respectively 1 microl with split injection (split ratio, 1:40) were compared. It was demonstrated that splitless injections of 1 microl, 2 microl, and 4 microl could be employed in the developed method, while split injection and splitless injections of 0.2 microl should be avoided.

7.
Forensic Sci Int ; 149(2-3): 219-29, 2005 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-15749364

RESUMEN

Reference material was synthesised for 21 substances that are frequently present as synthetic impurities, i.e. by-products, in illicitly produced amphetamine. Each of these substances is a typical by-product for at least one of the three approaches most often used to synthesise amphetamine, namely, the Leuckart, the reductive amination of benzyl methyl ketone, and the nitrostyrene routes. A large body of data on the substances was recorded, including the following: mass spectra, ultraviolet spectra, Fourier transform infrared spectra, infrared spectra in gas phase, and 1H NMR and 13C NMR spectra.

8.
Forensic Sci Int ; 149(2-3): 231-41, 2005 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-15749365

RESUMEN

The present study focused on the stability of 22 amphetamine impurities dissolved in six organic solvents: isooctane, toluene, ethanol, dichloromethane, ethyl acetate, and diethyl ether. The aim was to find the most inert, and thereby most suitable, solvent for amphetamine profiling. Mixtures of the impurities were prepared in the different solvents, and changes in the concentrations of the individual compounds over-time were monitored by gas chromatographic analysis after 0, 4, 12, 24, 48, and 96 h. Isooctane and toluene provided the most inert conditions, although, a few of the impurities were insufficiently stable in these two solvents. The present experiments were performed as a part of the development of a harmonized method for profiling of amphetamine. The results can be used to support the choice of organic solvents for sample preparation. They also provide information about the stability of the impurities that are found in profiles of illicit amphetamine. This is essential due to the fact, that unstable compounds can have a negative influence on the comparison of profiles.

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