Automated detection and classification of counterfeit banknotes using quantitative features captured by spectral-domain optical coherence tomography

Counterfeiting of banknotes is still a severe crime problem in many countries. One of the most significant issue for solving the crime is to classify the counterfeit types and identify the sources. Most of the current methods to classify counterfeit banknotes rely on manual examination that is time-consuming and labor-intensive. Moreover, these methods only detect surface features which can be easily imitated through advanced printing technology. In this study, an automated method based on optical coherence tomography (OCT) and machine-learning algorithms was proposed to classify different types of banknotes based on the internal features. A spectral-domain OCT (SD-OCT) system was employed for sub-surface imaging and quantitative assessment of banknotes. A total of 29 Chinese 100-Yuan banknotes were collected, in which 4 of them were real and 25 of them were counterfeiting by three different printing processes. Each banknote was imaged 10 times in 3 distinct regions, which resulted in a dataset of 290 samples. Each sample was characterized by extracting 2 A-scan (OCT signal intensity along depth) based features and 14B-scan (cross-sectional OCT images) based features. Several machine-learning models, including logistic regression (LR), support vector machines (SVM), K-nearest neighbor (KNN) and random forest (RF), were built and optimized as the classifiers that were trained using 203 samples and applied to predict 87 testing samples. The best performance was achieved by SVM classifier in which the sensitivity of 96.55% and specificity of 98.85% were obtained in discriminating between authentic and counterfeit banknotes, and the sensitivity of 94.67% and specificity of 98.22% were obtained in predicting the types of counterfeit banknotes. These classifiers were also evaluated using the receiver operating characteristic (ROC) curves. To the best of our knowledge, this is the first study where A-scan and B-scan derived features from OCT images have been used for the detection and classification of different types of counterfeit banknotes.     

ENFSI collaborative testing programme for ignitable liquid analysis: a review

The Fire and Explosion Investigation Working Group of the European Network of Forensic Science Institutes (ENFSI) is the organiser of a collaborative testing programme for ignitable liquid analysis. The testing programme was initiated in 1998. Initially to inventory the analytical methods used in this field of analysis, but with the ultimate goal to establish a European testing programme for fire debris analysts. As of today, five tests have been conducted. This article will provide an overview of the first five ENFSI collaborative tests for ignitable liquid analysis. The background, objectives and characteristics of the testing programme are summarised, followed by an overview of the sample composition employed, the participants' performance, the difficulties and the lessons learned in each test.     

The Effect of Alcohol‐Based Hand Sanitizer Vapors on Evidential Breath Alcohol Test Results

This study was undertaken to determine if the application of alcohol‐based hand sanitizers (ABHSs) to the hands of a breath test operator will affect the results obtained on evidential breath alcohol instruments (EBTs). This study obtained breath samples on three different EBTs immediately after application of either gel or foam ABHS to the operator's hands. A small, but significant, number of initial analyses (13 of 130, 10%) resulted in positive breath alcohol concentrations, while 41 samples (31.5%) resulted in a status code. These status codes were caused by ethanol vapors either in the room air or their inhalation by the subject, thereby causing a mouth alcohol effect. Replicate subject samples did not yield any consecutive positive numeric results. As ABHS application can cause a transitory mouth alcohol effect via inhalation of ABHS vapors, EBT operators should forego the use of ABHS in the 15 min preceding subject testing.     

Evaluation of the catalytic decomposition of H2O2 through use of organo-metallic complexes--a potential link to the luminol presumptive blood test

Hair testing for drugs of abuse is performed in Lombardy by eleven analytical laboratories accredited for forensic purposes, the most frequent purposes being driving license regranting and workplace drug testing. Individuals undergoing hair testing for these purposes can choose the laboratory in which the analyses have to be carried out. The aim of our study was to perform an interlaboratory exercise in order to verify the level of standardization of hair testing for drugs of abuse in these accredited laboratories; nine out of the eleven laboratories participated in this exercise. Sixteen hair strands coming from different subjects were longitudinally divided in 3-4 aliquots and distributed to participating laboratories, which were requested to apply their routine methods. All the participants analyzed opiates (morphine and 6-acetylmorphine) and cocainics (cocaine and benzoylecgonine) while only six analyzed methadone and amphetamines (amphetamine, methamphetamine, MDMA, MDA and MDEA) and five Δ(9)-tetrahydrocannabinol (THC). The majority of the participants (seven labs) performed acidic hydrolysis to extract the drugs from the hair and analysis by GC-MS, while two labs used LC-MS/MS. Eight laboratories performed initial screening tests by Enzyme Multiplied Immunoassay Technique (EMIT), Enzyme-linked Immunosorbent Assay (ELISA) or Cloned Enzyme Donor Immunoassay (CEDIA). Results demonstrated a good qualitative performance for all the participants, since no false positive results were reported by any of them. Quantitative data were quite scattered, but less in samples with low concentrations of analytes than in those with higher concentrations. Results from this first regional interlaboratory exercise show that, on the one hand, individuals undergoing hair testing would have obtained the same qualitative results in any of the nine laboratories. On the other hand, the scatter in quantitative results could cause some inequalities if any interpretation of the data is required.     

New trends in hair analysis and scientific demands on validation and technical notes

This review focuses on basic aspects of method development and validation of hair testing procedures. Quality assurance is a major issue in drug testing in hair resulting in new recommendations, validation procedures and inter-laboratory comparisons. Furthermore recent trends in research concerning hair analysis are discussed, namely mechanisms of drug incorporation and retention, novel analytical procedures (especially ones using liquid chromatography-mass spectrometry (LC-MS) and alternative sample preparation techniques like solid-phase microextraction (SPME)), the determination of THC-COOH in hair samples, hair testing in drug-facilitated crimes, enantioselective hair testing procedures and the importance of hair analysis in clinical trials. Hair testing in analytical toxicology is still an area in need of further research.     

External quality assessment schemes for toxicology

A variety of external quality assurance (EQA) schemes monitor quantitative performance for routine biochemical analysis of agents such as paracetamol, salicylate, ethanol and carboxyhaemoglobin. Their usefulness for toxicologists can be lessened where the concentrations monitored do not extend fully into the toxic range or where the matrix is synthetic, of animal origin or serum as opposed to whole human blood. A scheme for quantitative determinations of a wider range of toxicological analytes such as opioids, benzodiazepines and tricyclics in human blood has been piloted by the United Kingdom National External Quality Assessment Scheme (UKNEQAS). Specialist schemes are available for drugs of abuse testing in urine and for hair analysis. Whilst these programmes provide much useful information on the performance of analytical techniques, they fail to monitor the integrated processes that are needed in investigation of toxicological cases. In practice, both qualitative and quantitative tests are used in combination with case information to guide the evaluation of the samples and to develop an interpretation of the analytical findings that is used to provide clinical or forensic advice. EQA programs that combine the analytical and interpretative aspects of case studies are available from EQA providers such as UKNEQAS and the Dutch KKGT program (Stichting Kwaliteitsbewaking Klinische Geneesmiddelanalyse en Toxicologie).     

The U.S. Mandatory Guidelines for Federal Workplace Drug Testing Programs: current status and future considerations

The U.S. Department of Health and Human Services (HHS) drug testing standards were published in 1988 and revised in 1994, 1998, and 2004. In 2004, significant revisions defining, standardizing, and requiring specimen validity testing on Federal employee donor urine specimens were included. In a separate notice, HHS proposed to establish scientific and technical guidelines for the Federal Workplace Drug Testing Program to: (1) permit laboratory testing of hair, oral fluid, and sweat patch specimens in addition to urine specimens for marijuana, cocaine, phencyclidine, opiates (with focus on heroin), and amphetamines [including methylenedioxymethamphetamine (MDMA), methylenedioxyethamphetamine (MDEA), methylenedioxyamphetamine (MDA)]; (2) permit use of on-site point of collection test (POCT) devices to test urine and oral fluid at collection sites; (3) permit use of instrumented initial test (screening only) facilities [IITF] to quickly identify negative specimens; and (4) add training requirement for collectors, on-site testers, and MROs. This proposal was published in the Federal Register on 13 April 2004, with a 90-day public comment period. The Substance Abuse and Mental Health Services Administration, HHS, reviewed those comments and is preparing the Final Notice that will define the requirements for such testing, including: specimen collection procedures, custody and control procedures that ensure donor specimen identity and integrity, testing facility, initial and confirmatory test cutoff concentrations, analytical testing methods, result review and reporting, evaluation of alternative medical explanations for presence of drug or metabolite in the donor's specimen, and laboratory certification issues. Voluntary pilot performance testing (PT) programs for each specimen type are on-going since April 2000 to determine how to prepare PT materials for specimens other than urine to evaluate laboratories' ability to routinely achieve accuracy and precision required. Certification programs will be developed using the current urine drug testing National Laboratory Certification Program model. The addition of accurate and reliable workplace drug testing using hair, oral fluid, and sweat patch specimens will complement urine drug testing, and aid in combating industries devoted to suborning drug testing through adulteration, substitution, and dilution. For example, hair testing may detect chronic drug use for up to 90 days and be useful in pre-employment situations; oral fluid testing may detect drug use in past hours and be useful in post-accident situations; sweat patch testing may be useful in follow-up drug testing and treatment programs; POCTs and IITFs may be most useful for quickly identifying specimens that are negative for drugs and indicate that the specimen is valid.     

兔尿中敌鼠及其代谢物的HPLC-DAD分析

目的 尿中敌鼠及其代谢物的HPLC分析方法研究。方法 用CN柱和SAX柱的固相萃取(SPE)技术分离提取兔尿中的敌鼠及其代谢物,用香豆素作内标,用HPLC-DAD方法进行fenxi。色谱柱:Hypersil BDSC_(18)(150×4.6mm):保护柱:Phenomenex C_(18) (ODS,4×3.0mm,Octadecyl;流动相A:0.5％离子对A水溶液,B:0.5%离子对A甲醇液,梯度程序洗脱;DAD检测波长为311nm。结果 在中毒的兔尿中检出11种敌鼠代谢物。结论 此方法简单、准确、快速。     

SARM-S4 and metabolites detection in sports drug testing: a case report

Recently, pharmaceutical industry developed a new class of therapeutics called Selective Androgen Receptor Modulator (SARM) to substitute the synthetic anabolic drugs used in medical treatments. Since the beginning of the anti-doping testing in sports in the 1970s, steroids have been the most frequently detected drugs mainly used for their anabolic properties. The major advantage of SARMs is the reduced androgenic activities which are the main source of side effects following anabolic agents' administration. In 2010, the Swiss laboratory for doping analyses reported the first case of SARMs abuse during in-competition testing. The analytical steps leading to this finding are described in this paper. Screening and confirmation results were obtained based on liquid chromatography tandem mass spectrometry (LC-MS/MS) analyses. Additional information regarding the SARM S-4 metabolism was investigated by ultra high-pressure liquid chromatography coupled to quadrupole time-of-flight mass spectrometer (UHPLC-QTOF-MS).     

Evidence on unusual way of cocaine smuggling: cocaine-polymethyl methacrylate (PMMA) solid solution--study of clandestine laboratory samples

An abandoned clandestine laboratory was seized in Slovenia. All confiscated exhibits were analysed in a forensic laboratory, where the following analytical methods were applied: capillary gas chromatography coupled with mass spectrometry (GC-MS) combined also by solid-phase micro extraction (SPME) and pyrolysis (Py) technique, Fourier transform infrared spectrometry (FTIR) and scanning electron microscopy with energy dispersive X-ray detector (SEM-EDX). The most interesting analytical findings can be summarised as follows: at the crime scene some plastic pieces, which contained cocaine dissolved (as solid solution) in polymethyl methacrylate-plexiglass (PMMA), were found. The highest cocaine concentration measured in the plastic sample was about 15% by weight. Two larger lumps of material (12 and 3 kg) were composed mainly of PMMA and CaCO3 and contained only 0.4 and 0.5% of cocaine, respectively. As for the low cocaine concentration, we assume that those two lumps of material represent discarded waste product--residue after the isolation of cocaine from plastic. Higher quantities of pure solvents (41 l) and solvent mixtures (87 l) were seized. We identified three types of pure solvents (acetone, gasoline and benzine) and two different types of solvent mixtures (benzine/acetone and gasoline/acetone). The total seized volume (87 l) of solvent mixtures holds approximately 395 g of solid residue formed mainly of PMMA and cocaine. Obviously solvent mixtures were used for isolation of cocaine from the plastic. Small quantities of relatively pure cocaine base were identified on different objects. There were two cotton sheets, most probably used for filtration. One sheet had traces of cocaine base (76% purity) on the surface, while cocaine in hydrochloride form (96%) was identified on the other sheet. GC-MS analyses of micro traces isolated from analytical balances showed the presence of cocaine and some common adulterants: phenacetine, lidocaine and procaine. A cocaine sample compressed in the shape of block was also seized. The above analytical findings inferred us to the conclusion that the illicit laboratory was used for the isolation of cocaine from PMMA resin. Further more, analyses confirm that not only isolation but also further manipulation of cocaine, i.e. adulteration/dilution, as well as the formation of cocaine blocks took place in the house. The information obtained through analyses also allowed us to make some hypotheses about possible multistage isolation procedure.     

The use of hair as a toxicological tool in DFC casework

When drugging related offences are cited, most people think of sexual assault. However, the law covers any crime committed whilst the complainant is under the influence of alcohol or drugs i.e. the use of a drug to modify a person's behaviour for criminal gain. The case types encountered include robbery, blackmail and of course sexual offences.Hair analysis for drugs is now well established in Forensic Toxicology. Its use as an analytical tool in workplace testing, post-mortem toxicology and criminal cases is expanding both in the UK and worldwide, and it is now widely accepted as an alternative or complimentary matrix for these cases. This paper will provide a brief overview of hair testing in cases of Drug Facilitated Crime stressing the importance of timely sample collection. Its usefulness in cases of this type will be highlighted through case examples.     

Performance of forensic facial comparison by morphological analysis across optimal and suboptimal CCTV settings

Facial comparison is an important yet understudied discipline in forensics. The recommended method for facial comparison in a forensic setting involves morphological analysis (MA) with the use of a facial feature list. The performance of this approach has not been tested across various closed-circuit television (CCTV) conditions. This is of particular concern as video and image data available to law enforcement is often varied and of subpar conditions. The present study aimed at testing MA across two types of CCTV data, representing ideal and less than ideal settings, also assessing which particular shortcomings arose from less-than-ideal settings. The study was conducted on a subset of the Wits Face Database arranged in a total of 225 face pools. Each face pool consisted of a target image obtained from either a high-definition digital CCTV camera or a low-definition analogue CCTV camera in monochrome, contrasted to 10 possible matches. The face pools were analysed and scored using MA and confusion matrices were used to analyse the outcomes. A notably high chance corrected accuracy (CCA) (97.3%) and reliability (0.969) was identified across the digital CCTV sample, while in the analogue CCTV sample MA appeared to underperform both in accuracy (CCA: 33.1%) and reliability (0.529). The majority of the errors in scoring resulted in false negatives in the analogue sample (75.2%), while across both CCTV conditions false positives were low (digital: 0.3%; analogue: 1.2%). Even though hit rates appeared deceptively high in the analogue sample, the various measures of performance used and particularly the chance corrected accuracy highlighted its shortfalls. Overall, CCTV recording quality appears closely associated to MA performance, despite the favourable error rates when using the Facial Identification Scientific Working Group feature list.     

Drug-facilitated sexual assault involving gamma-hydroxybutyric acid

The first case involving an alleged sexual assault linked to the use of gamma-hydroxybutyric acid (GHB) in Oklahoma is reported. A-48-year-old Caucasian woman taking amitriptyline was known to have voluntarily ingested a sports drink containing a relaxing health product. She purportedly experienced unconsciousness that persisted for approximately 4 h. The toxicological testing on urine identified GHB, amitriptyline, and nortriptyline using a capillary Hewlett-Packard 6890 gas chromatograph coupled to a Hewlett-Packard 5973 mass selective detector (MSD). The GHB concentration in urine was 26.9 microg/mL. Urine concentrations of amitriptyline and nortriptyline were not determined. The analytical method used for identifying and quantitating GHB can be applied to matters of forensic interests.     

Chemical Enhancement Techniques of Bloodstain Patterns and DNA Recovery After Fire Exposure*

Abstract: It is common in forensic casework to encounter situations where the suspect has set a fire to cover up or destroy possible evidence. While bloodstain pattern interpretation, chemical enhancement of blood, and recovery of deoxyribonucleic acid (DNA) from bloodstains is well documented in the literature, very little information is known about the effects of heat or fire on these types of examinations. In this study, a variety of known types of bloodstain patterns were created in a four‐room structure containing typical household objects and furnishings. The structure was allowed to burn to flashover and then it was extinguished by firefighters using water. Once the structure cooled over night, the interior was examined using a bright light. The bloodstains were evaluated to see if the heat or fire had caused any changes to the patterns that would inhibit interpretation. Bloodstain patterns remained visible and intact inside the structure and on furnishings unless the surface that held the blood was totally burned away. Additionally, a variety of chemical techniques were utilized to better visualize the patterns and determine the possible presence of blood after the fire. The soot from the fire formed a physical barrier that initially interfered with chemical enhancement of blood. However, when the soot was removed using water or alcohol, the chemicals used, fluorescein, luminol, Bluestar^®, and Hemastix^®, performed adequately in most of the tests. Prior to DNA testing, the combined phenolphthalein/tetramethyl benzidine presumptive test for the presence of blood was conducted in the laboratory on samples recovered from the structure in an effort to assess the effectiveness of using this type of testing as a screening tool. Test results demonstrated that reliance on obtaining a positive presumptive result for blood before proceeding with DNA testing could result in the failure to obtain useful typing results. Finally, two DNA recovery methods (swabbing the stain plus cutting or scraping the stain) were attempted to evaluate their performance in recovering samples in an arson investigation. Recovery of DNA was more successful in some instances with the swabbing method, and in other instances with the cutting/scraping method. Therefore, it is recommended that both methods be used. For the most part, the recovered DNA seemed to be unaffected by the heat, until the temperature was 800°C or greater. At this temperature, no DNA profiles were obtained.     

Examining the effect of dl-3,4-methylenedioxymethamphetamine (MDMA) and methamphetamine on the Standardized Field Sobriety Tests

dl-3,4-methylenedioxymethamphetamine (MDMA) and methamphetamine are commonly used illicit drugs that are thought to impair driving ability. The Standardized Field Sobriety Tests (SFSTs) are utilized widely to detect impairment associated with drugs other than alcohol in drivers, although limited evidence concerning MDMA and methamphetamine consumption on SFST performance exists. The aim of this study was to evaluate whether the SFSTs were a sensitive measure for identifying the presence of the specific isomer d-methamphetamine and MDMA. In a double-blind, within-subject, counter-balanced and placebo-controlled study, 58 healthy and abstinent recreational drugs users were administered three treatments: 100mg of MDMA, 0.42 mg/kg d-methamphetamine, and placebo. For each condition the SFSTs were administered at 4 and 25 h post treatment. d-methamphetamine was not found to significantly impair SFST performance unlike MDMA, which significantly impaired SFST performance in comparison to placebo with 22% of the sample failing the test at the 4h testing time-point. No differences were observed at the 25 h testing time-point for any of the conditions. It was concluded that the SFSTs are not efficient in identifying the presence of low level d-methamphetamine, and are significantly better at detecting the presence of MDMA at the levels assessed.     

Multi-technique comparison of source and primary transfer soil samples: an experimental investigation.

The comparison of soil samples is of long-standing and increasing interest in forensic science. Routine comparisons should involve the use of several techniques in combination. A wide range of analytical techniques can be used, choice being dependent on several factors including sample size and character, time constraints and cost limitations. In this paper results are presented for experiments carried out to test the effectiveness of four of the available analytical techniques (spectro-photometric colour determination, laser diffraction particle size analysis, stable isotope analysis and chemical element analysis) used to compare single source and primary transfer soil samples. Four soil types and five footwear types were used. All four techniques showed excellent precision and good resolving power between soil types. Only relatively small differences were obtained between source and transferred soil samples in terms of colour, stable carbon and nitrogen isotope ratios and elemental chemistry. Slight but significant differences were found in grain size, indicating that the primary transfer process is to some extent grain size selective.     

Chapter 13: Traumatic Brain Lesions

Cranial traumas are often encountered in wartime. The statistics of different countries show a rise in the frequency of traumas in the past few decades. This is understandable considering the development of all types of transportation and the widespread use of machines in agriculture and industry.     

HAIRVEQ: an external quality control scheme for drugs of abuse analysis in hair

The Istituto Superiore di Sanità of Rome, Italy, in cooperation with Institut Municipal d'Investigaciò Mèdica of Barcelona, Spain, set up an external quality control program (HAIRVEQ) to evaluate reliability in hair testing for drug abuse by laboratories from the Italian National Health Service. Samples included in the program were real hair samples from drugs consumers. Prior to sending, hair samples were reduced to powdered form, mixed to ensure homogeneity and tested with GC/MS by four Reference Laboratories. Up to now, four different exercises have been concluded and 23 laboratories participated. Samples containing high and low concentrations of opiates, cocaine and metabolites, low concentrations of MDMA and two blank samples, were included in the intercomparison exercises performed in the first year of HAIRVEQ activities. Results show an insufficient performance of participating laboratories. About 82% of laboratories reported incorrect results on a qualitative basis (false positive and false negative results) for some of the submitted samples. More than one-half of laboratories reported quantitative results (60%). On the basis of the calculated z scores, only between 35 and 55% of results reported should be considered as satisfying. Guidelines have to be provided by Italian authorities for method validation as well as set of recommended cut-off concentrations to orientate laboratories in their quality objectives when developing analytical methodologies as tools to improve reliability and consequently performance of hair analysis.