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1.
A method for the identification of 3,4‐methylenedioxymethamphetamine (MDMA) and meta‐chlorophenylpiperazine (mCPP) was developed employing capillary electrophoresis (CE) with capacitively coupled contactless conductivity detection (C4D). Sample extraction, separation, and detection of “Ecstasy” tablets were performed in <10 min without sample derivatization. The separation electrolyte was 20 mm TAPS/Lithium, pH 8.7. Average minimal detectable amounts for MDMA and mCPP were 0.04 mg/tablet, several orders of magnitude lower than the minimum amount encountered in a tablet. Seven different Ecstasy tablets seized in Rio de Janeiro, Brazil, were analyzed by CE‐C4D and compared against routine gas chromatography‐mass spectrometry (GC‐MS). The CE method demonstrated sufficient selectivity to discriminate the two target drugs, MDMA and mCPP, from the other drugs present in seizures, namely amphepramone, fenproporex, caffeine, lidocaine, and cocaine. Separation was performed in <90 sec. The advantages of using C4D instead of traditional CE‐UV methods for in‐field analysis are also discussed.  相似文献   

2.
Cycads in South Africa are facing an extinction crisis due to the illegal extraction of plants from the wild. Proving wild origin of suspect ex situ cycads to the satisfaction of a court of law is difficult, limiting law enforcement efforts. We investigated the feasibility of using multiple stable isotopes to identify specimens removed from the wild. Relocated and wild specimens from two species in the African genus Encephalartos (E. lebomboensis and E. arenarius) were sampled. 14C analysis indicated that a ± 30‐year chronology could be reliably obtained from the cycads. For E. arenarius, pre‐relocation tissue was consistent with a wild origin, whereas tissue grown post‐relocation was isotopically distinct from the wild for 87Sr/86Sr and δ15N. For E. lebomboensis, δ34S, δ18O, and 87Sr/86Sr were different between relocated and control plants, consistent with the >30 years since relocation. Our findings demonstrate the potential for a forensic isotope approach to identify illegal ex situ cycads.  相似文献   

3.
Research examining detection of verbal deception reveals that lay observers generally perform at chance. Yet, in the criminal justice system, laypersons that have not undergone specialist investigative training are frequently called upon to make veracity judgements (e.g., solicitors; magistrates; juries). We sought to improve performance by manipulating the timing of information revelation during investigative interviews. A total of 151 participants played an interactive computer game as either a truth‐teller or a deceiver, and were interviewed afterwards. Game information known to the interviewer was revealed either early, at the end of the interview, or gradually throughout. Subsequently, 30 laypersons individually viewed a random selection of interviews (five deceivers and five truth‐tellers from each condition), and made veracity and confidence judgements. Veracity judgements were most accurate in the gradual condition, < .001, η2 = .97 (above chance), and observers were more confident in those judgements, < .001, η2 = .99. Deceptive interviewees reported the gradual interviews to be the most cognitively demanding, < .001; η2 = .24. Our findings suggest that the detection of verbal deception by non‐expert observers can be enhanced by employing interview techniques that maximize deceivers' cognitive load, while allowing truth‐tellers the opportunity to respond to evidence incrementally.  相似文献   

4.
This study examines the reliability of age estimation utilizing the Greulich and Pyle atlas in relation to a modern Scottish population. A total of 406 left‐hand/wrist radiographs (157 females and 249 males) were age‐assessed using the Greulich and Pyle atlas. Analysis showed that there was a strong correlation between chronological age and estimated age (females R2 = 0.939, males R2 = 0.940). When age groups were broken down into year cohorts, the atlas over‐aged females from birth until 13 years of age. The pattern for males showed that the atlas under‐estimated age until 13 years of age after which point it consistently over‐aged boys between 13 and 17 years of age. This study showed that the Greulich and Pyle atlas can be applied to a modern population but would recommend that any analysis takes into account the potential for over‐ and under‐aging shown in this study.  相似文献   

5.
A nontargeted approach based on liquid chromatography equipped with a quadrupole time‐of‐flight mass detector (LC‐MS Q‐TOF) joined to nuclear magnetic resonance (NMR) analysis allowed rapid identification and quantification of the anti‐inflammatory drug aceclofenac in illegal Adderall tablets. The largest chromatographic peak had m/z = 354.030 and m/z = 376.012 matching, respectively, the ionic structures (M + H)+ and (M + Na)+ of a molecule M. The accurate mass data generated the molecular formula C16H13Cl2NO4. A screening of the pharmaceutical active substances having that molecular formula together with the MS/MS fragmentation pattern suggested aceclofenac. Aceclofenac structure was unambiguously confirmed by 1H and 13C NMR experiments. The aceclofenac content was 90 mg/tablet (RSD 2%) as detected by quantitative NMR. Information on the identity and content of illegal drugs is required for legal purposes; it supports in evaluating the effective impact on users safety, and it is useful for control laboratories using a targeted approach in their analytical activities.  相似文献   

6.
Methamphetamine (MA) tablet production confers chemical and physical properties. This study developed a simple and effective physical characteristic profiling method for MA tablets with capital letter “WY” logos, which realized the discrimination between linked and unlinked seizures. Seventeen signature distances extracted from the “WY” logo were explored as factors for multivariate analysis and demonstrated to be effective to represent the features of tablets in the drug intelligence perspective. Receiver operating characteristic (ROC) curve was used to evaluate efficiency of different pretreatments and distance/correlation metrics, while “Standardization + Euclidean” and “Logarithm + Euclidean” algorithms outperformed the rest. Finally, hierarchical cluster analysis (HCA) was applied to the data set of 200 MA tablet seizures randomly selected from cases all around China in 2015, and 76% of them were classified into a group named after “WY‐001.” Moreover, the “WY‐001” tablets occupied 51–80% tablet seizures from 2011 to 2015 in China, indicating the existence of a huge clandestine factory incessantly manufacturing MA tablets.  相似文献   

7.
Juvenile sex offenders (JSO) are a specific subset of delinquent adolescents that are receiving more attention because of the crimes they commit and the issues surrounding how to successfully treat their deviant behaviors. Given JSO are such predominant treatment concerns in society, it is essential to identify and target key risk factors. One sexual behavior, bestiality, may be of particular importance to address in treatment. In a meta‐analysis conducted by Seto and Lalumiere, a 14% rate of bestiality among JSO was reported. This current study examined the differences in JSO (n = 32) who admitted bestiality based upon a self‐report measure, the Multiphasic Sexual Inventory‐II (MSI‐II), compared to information elicited by polygraphs. The results indicated extensive underreporting of bestiality behaviors between these two sources of information (MSI‐II = 37.5%; polygraph = 81.25%). These findings are important given the reliance treatment programs place on information elicited from self‐report tools.  相似文献   

8.
Abstract: Detection of mass graves utilizing the hyperspectral information in airborne or satellite imagery is an untested application of remote sensing technology. We examined the in situ spectral reflectance of an experimental animal mass grave in a tropical moist forest environment and compared it to an identically constructed false grave which was refilled with soil, but contained no cattle carcasses over the course of a 16‐month period. The separability of the in situ reflectance spectra was examined with a combination of feature selection and five different nonparametric pattern classifiers. We also scaled up the analysis to examine the spectral signature of the same experimental mass grave from an air‐borne hyperspectral image collected 1 month following burial. Our results indicate that at both scales (in situ and airborne), the experimental grave had a spectral signature that was distinct and therefore detectable from the false grave. In addition, we observed that vegetation regeneration was severely inhibited over the mass grave containing cattle carcasses for up to a period of 16 months. This experimental study has demonstrated the real utility of airborne hyperspectral imagery for the detection of a relatively small mass grave (5 m2) within a specific climatic zone. Other climatic zones will require similar actualistic modeling studies, but it is clear that the applications of this technology provide the international community with both an early detection tool and a tool for ongoing monitoring.  相似文献   

9.
The content of ecstasy tablets has been changing over the years, and nowadays 3,4‐methylenedioxymethamphetamine (MDMA) is not always present in the tablets. The aim of this study was to investigate the chemical composition in the seized tablets labeled as ecstasy. We analyzed samples from 150 different seizures made by Sao Paulo's State Police by gas chromatography–mass spectrometry. MDMA was present in 44.7% of the analyzed samples, and another twenty different active substances were identified in these tablets, such as caffeine, 2C‐B, piperazines, amphetamines, phencyclidine, and others. Methamphetamine was present in 22% of these samples. The results demonstrate a huge shift in the pattern of trafficking of synthetic drugs, where MDMA has been replaced in tablets mostly by illicit psychoactive substances, in a clear attempt to bypass the law. The great variability in the tablets composition may lead to an increased risk of drug poisoning.  相似文献   

10.
A portable capillary electrophoresis instrument with dual capacitively coupled contactless conductivity detection (C4D) was used to determine the inorganic ionic profiles of three pharmaceutical samples and precursors of two illicit drugs (contemporary samples of methylone and para‐methoxymethamphetamine). The LODs ranged from 0.10 μmol/L to 1.25 μmol/L for the 10 selected cations, and from 0.13 μmol/L to 1.03 μmol/L for the eight selected anions. All separations were performed in less than 6 min with migration times and peak area RSD values ranging from 2 to 7%. The results demonstrate the potential of the analysis of inorganic ionic species to aid in the identification and/or differentiation of unknown tablets, and real samples found in illicit drug manufacture scenarios. From the resulting ionic fingerprint, the unknown tablets and samples can be further classified.  相似文献   

11.
In forensic diagnosis, postmortem blood glucose is known to be susceptible to change after death. However, the 1,5‐anhydroglucitol (1,5‐AG) concentrations in plasma and cerebrospinal fluid (CSF) reflect the mean blood glucose level for a short period of time. In this study, we compared the postmortem 1,5‐AG concentrations in vitreous humor and CSF in 47 subjects to evaluate the utility of this concentration in the vitreous humor for forensic diagnosis. The postmortem 1,5‐AG concentrations in vitreous humor (mean±SD: 20.2 ± 8.7 μg/mL) and CSF (16.8 ± 8.7 μg/mL) did not differ significantly and showed a strong correlation (r2 = 0.87, p < 0.01). These results suggest that the vitreous humor 1,5‐AG concentration provides useful information on the antemortem blood glucose level, in addition to the HbA1c value and the CSF 1,5‐AG concentration.  相似文献   

12.
Recently, 3,4-methylenedioxyamphetamine derivatives have been encountered in the Italian illicit market, mainly in form of tablets. Among this class of substances small modifications of the molecule may result in a wide range of derivatives and analogs some of which are not yet listed as controlled substances in the Italian schedules. Due to the structural similarity some of these molecules have a gas chromatographic behavior and mass spectra that only slightly differ. In the present work, an analytical strategy is proposed to achieve the identification of analogs within this class of molecules. In seized material sent by the Court of Law of Rome to our laboratories a number of tablets engraved with different symbols (e.g., `Dollar', `Fido Dido' and `Bomb') were submitted to analysis in order to establish whether they contained drugs of abuse. The analytical techniques employed for this purpose were UV spectrophotometry and thin-layer chromatography which provided information suggesting that the tablets contained a methylenedioxyamphetamine. Gas chromatography with flame ionization detection indicated that the main ingredient differed from the molecules of the same class already known. Finally, capillary gas chromatographic–mass spectrometric analysis of the native molecules and their pentafluoropropionic acid derivatives, performed with both, electron impact and chemical ionization, allowed the identification, in each tablet, of three molecules: the N-methyl-1-(3,4-methylenedioxyphenyl)-2-butanamine (MDP-2-MB, MBDB), the 1-(3,4-methylenedioxyphenyl)-2-butanamine (MDP-2-B) and the N,N-dimethyl-1-(3,4-methylenedioxyphenyl)-2-butanamine (MDP-2-MMB).  相似文献   

13.
Most narcotics‐related cases in the United States involve Cannabis sativa. Material is typically identified based on the cystolithic hairs on the leaves and with chemical tests to identify of the presence of cannabinoids. Suspect seeds are germinated into a viable plant so that morphological and chemical tests can be conducted. Seed germination, however, causes undue analytical delays. DNA analyses that involve the chloroplast and nuclear genomes have been developed for identification of C. sativa materials, but they require several nanograms of template DNA. Using the trnL 3′ exon‐trnF intragenic spacer regions within the C. sativa chloroplast, we have developed a real‐time quantitative PCR assay that is capable of identifying picogram amounts of chloroplast DNA for species determination of suspected C. sativa material. This assay provides forensic science laboratories with a quick and reliable method to identify an unknown sample as C. sativa.  相似文献   

14.
DNA on drugs     
The use of illicit drugs is a continuing blight on society. Detecting DNA from individuals involved in the manufacturing and distribution of drugs can provide valuable investigative information or strategic intelligence which, in turn, can be used to disrupt the supply and distribution of illicit drugs. Our study details the transfer, persistence, prevalence, and recovery of human DNA on the exterior of tablets and capsules, as well as within drug powders. Various experiments were conducted to mimic stages in the creation and packaging of tablets and capsules. We showed that the act of brief contact (1–3 s) is sufficient to generate informative DNA profiles that can be uploaded and compared to databases internationally. This work complements chemical drug profiling data by linking seizures to each other and individuals via DNA profiles, providing information to prosecution or intelligence agencies. The generation of DNA information from illicit drug preparations is another tool that can be used in the fight against illicit drug manufacture and distribution.  相似文献   

15.
Artemisia absinthium (wormwood), a common ingredient in absinthe, contains the compound thujone, which is unregulated by the U.S. Drug Enforcement Agency. Thujone can cause an “unregulated legal high” in higher concentrations. The European Union limits thujone from Artemisia species to 35 mg/kg while the U.S. Food and Drug Administration requires less than 10 ppm to be “thujone‐free.” However, individuals can smoke or ingest A. absinthium in different forms. This study developed a polymerase chain reaction (PCR) high‐resolution melt (HRM) assay to detect and identify A. absinthium based on primer specificity, sensitivity, repeatability, and robustness. A triplex assay was performed with three “unregulated legal high” species: Datura stramonium, Merremia tuberosa, and A. absinthium; the PCR HRM assay detected and identified each plant at melt temperatures 77.42 ± 0.20°C, 83.88 ± 0.22°C, and 87.77 ± 0.15°C, respectively. The primer set developed distinguished A. absinthium from a variety of plant species and was successfully triplexed.  相似文献   

16.
Pink teeth is thought to result from the seepage of hemoglobin caused by dental pulp decomposition. We investigated whether racemization can be applied for age estimation in cases of pink teeth where the whole tooth is used. The pink teeth used were three cases and the normal teeth for control were five mandibular canines of known age. Age of the pink teeth was calculated on the basis of regression formula obtained from the five control teeth. Only a slight error was noted between the actual and estimated ages of the pink teeth (R2 = 0.980, r = 0.990): Cases 1–3 actually aged 23, 53, and 59 years were estimated to be 26, 52, and 60 years. Based on our results of testing pink teeth of known age, we suggest that racemization techniques allow for the age estimation of pink teeth using the same methods for normally colored teeth.  相似文献   

17.
A bead‐based liquid hybridization assay, Luminex® 100?, was used to identify four pathogenic bacteria, Bacillus anthracis, Clostridium botulinum, Francisella tularensis subsp. tularensis, and Yersinia pestis, and several close relatives. Hybridization between PCR‐amplified target sequences and probe sequences (located within the 23S ribosomal RNA gene rrl and the genes related to the toxicity of each bacterium) was detected in single‐probe or multiple‐probe assays, depending on the organism. The lower limits of detection (LLDs) for the probes ranged from 0.1 to 10 ng. Sensitivity was improved using lambda exonuclease to digest the noncomplementary target strand. All contributors in 33 binary, ternary, and quaternary mixtures in which all components were present in a 1:1 ratio were identified with an 80% success rate. Twenty‐eight binary mixtures in which the two components were combined in various ratios were further studied. All target sequences were detected, even when the minor component was overshadowed by a tenfold excess of the major component.  相似文献   

18.
In order to facilitate forensic intelligence efforts in managing large collections of physical feature data pertaining to illicit tablets, we have developed an automated shape classification method. This approach performs categorical shape annotation for the domain of illicit tablets. It is invariant to scale, rotation and translation and operates on digital images of seized tablets. The approach employs two processing levels. The first (coarse) level is being based on comparing the contour curvature space of tablet pairs. The second (fine) level is a rule based approach, implemented as a classification tree, that exploits characteristic similarities of shape categories. Annotation is demonstrated over a collection of 169 tablets selected for their diverse shapes with an accuracy of 97.6% when 19 shape categories are defined.  相似文献   

19.
Forensic evidence samples are routinely found as stains on various substrates, which may contain substances known to inhibit polymerase chain reaction (PCR). The goal of this study was to evaluate post‐Chelex®100 purification using powdered activated carbon (PAC). Mock crime scene DNA extracts were analyzed using quantitative PCR and short tandem repeat (STR) profiling to test the DNA recovery and inhibitor removal using PAC with those of the Amicon®Ultra 100K. For extracted bloodstains on soil and wood substrates, PAC and Amicon®Ultra 100K generated similar DNA yield and quality. Moreover, the two methods significantly decreased the concentration of humic substances and tannins compared to nonpurified extracts (< 0.001). In instances where extracts contained indigo dye (bloodstains on denim), Amicon®Ultra 100K performed better than PAC due to improved amplifiability. Efficient adsorption of humic substances and tannins, which are common inhibitors, indicates PAC's potential application in the purification of high‐template DNA extracts.  相似文献   

20.
Estimating age‐at‐death of individuals represented only by skeletonized human remains is a fundamental aspect of forensic anthropological casework. Recently, several researchers have proposed that bone mineral density (BMD) is a useful predictor of age‐at‐death in forensic contexts. Navega et al. (JFS 63(2):497–503) developed an online application called DXAGE for calculating age‐at‐death from BMD parameters. This study tests the utility of DXAGE by utilizing data from the National Health and Nutrition Examination Survey (NHANES). BMD data from a female subsample (n = 470) of the NHANES 2007–2008 dataset were analyzed, and the relationship between predicted age and real age was examined. Inaccuracy was 14.25 years, and bias was ?7.20 years. Results show that there is a weak correlation between predicted and actual age (r = 0.47) using the DXAGE application. While BMD data are potentially useful for predicting age age‐at‐death, the DXAGE application should be used cautiously in forensic anthropological contexts.  相似文献   

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