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1.
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   

2.
目的建立了鸦片中吗啡、可待因、蒂巴因、罂粟碱、那可汀5种常量生物碱和牛心果碱、劳丹宁、劳丹素等12种痕量生物碱同时分离鉴定的超高效液相色谱-高分辨四极杆飞行时间串联质谱(UPLC/Q-TOF)方法。方法采用Agilent Eclipse Plus C18RRHD(2.1 mm×100 mm,1.8μm)色谱柱,以10 mM甲酸铵溶液和乙腈体系梯度洗脱,使用ESI离子源,正离子模式下采集数据。结果借助UPLC的快速分离和Q-TOF-MS测定的精确分子量和二级碎片信息,实现了17种生物碱的检测。应用SIMCA-P软件对78份国产鸦片和200份缅甸产鸦片进行偏最小二乘法判别分析(partial least squaresdiscriminate analysis,PLS-DA),比较不同地区鸦片样品中生物碱的差异,建立了区分国产鸦片和缅甸产鸦片的判别方法。结论所建立的方法用于鸦片样品中常量和痕量生物碱的检测及鸦片样品的产地判别,具有快速、高效、灵敏、准确的特点。  相似文献   

3.
Assigning the gender of a DNA contributor in forensic analysis is typically achieved using the amelogenin test. Occasionally, this test produces false‐positive results due to deletions occurring on the Y chromosome. Here, a four‐marker “YFlag” method is presented to infer gender using single‐base extension primers to flag the presence (or absence) of Y‐chromosome DNA within a sample to supplement forensic STR profiling. This method offers built‐in redundancy, with a single marker being sufficient to detect the presence of male DNA. In a study using 30 male and 30 female individuals, detection of male DNA was achieved with c. 0.03 ng of male DNA. All four markers were present in male/female mixture samples despite the presence of excessive female DNA. In summary, the YFlag system offers a method that is reproducible, specific, and sensitive, making it suitable for forensic use to detect male DNA.  相似文献   

4.
Far too often, minority students are faced with punitive disciplinary actions and are consequently directed to the “school‐to‐prison” pipeline. From education to discipline, implementation of policies that criminalize minor delinquent behavior pushes these students out of school and into the juvenile justice system. Traditional disciplinary actions that would land students in the principal's office have gradually transformed to students being handcuffed and thrown in jail. This Note proposes a model statute requiring states with a high criminal delinquency rate to implement school‐based youth courts in public high schools.  相似文献   

5.
Synthetic tryptamines have gained popularity for their hallucinogenic properties, unscheduled status, and availability from “head shops” and through the internet. Here, we present a case of synthetic tryptamine‐induced delirium secondary to 5‐MeO‐DALT ingestion in a previously healthy young male. 5‐MeO‐DALT led to the hospitalization of our patient after ingestion of a standard dose, presenting with extreme agitation, tachycardia, diaphoresis, and combativeness leading to physical restraint and intravenous sedation. A search of PubMed, Ovid, and Google Scholar for keywords of “5‐MeO‐DALT,” “5‐methoxy‐N,N‐diallyltryptamine,” or “Lucy‐N‐Nate” found no case reports or clinical articles in the literature. Rapid emergence and commercialization of this novel synthetic tryptamine 5‐MeO‐DALT points to the importance of health care and forensic professionals keeping abreast of the latest drugs of abuse and their clinical features. The authors hope this report leads the way in disseminating the potential risks associated with unscheduled and unregulated substances, synthetic tryptamines such as 5‐MeO‐DALT in particular.  相似文献   

6.
Soil vestiges might provide information about a crime scene. The Rietveld method with X‐ray diffraction data (RM‐XRD) is a nondestructive technique that makes it possible to characterize minerals present in the soils. Soil clays from the metropolitan region of Curitiba (Brazil) were submitted to DCB treatment and analyzed using XRD with CuKα radiation in the step‐scan mode (0.02° 2θ/5 s). The GSAS+EXPGUI software was used for RM refinement. The RM‐XRD results, together with the principal component analysis (PCA) (52.6% total variance), showed the kaolinite predominance in most analyzed samples and the highest quartz contents in “site 1.” Higher anatase, and gibbsite and muscovite contents influenced discrimination, mainly in “site 3” and “site 1,” respectively. These results were enough to discriminate clays of four sites and two horizons using a reduced amount of sample showing that the technique can be applied to the investigation into soil vestiges.  相似文献   

7.
The information inherent in cigarette ash in the form of trace‐metal concentrations may be of use in a forensic context as it can indicate the brand from which the ash originated. This knowledge might help place suspects at crime scenes or determine how many people may have been present. To develop and test statistical models capable of classifying ash samples according to brand, commercial cigarettes procured in the U.S. and overseas were “smoked” using a peristaltic pump, mimicking the range of human smoking habits. Ash samples were digested in a mixture of nitric and hydrochloric acid applying microwave digestion and analyzed using inductively coupled plasma‐mass spectrometry. Principal component analysis of the elemental data showed intrinsic differences between brands. Partial least squares‐discriminant analysis demonstrated that brand classification yields good sensitivity and specificity for a number of models tested. Varying smoking parameters did not impact the classification of ash samples.  相似文献   

8.
The PE‐Swab direct STR amplification workflow was developed to process low‐level “touch DNA” samples. In this workflow, a forensic sample is first collected on a 4‐mm PE‐Swab (a novel sample collection device); two 2‐mm punches containing collected samples are then generated from the PE‐Swab and directly amplified for STR typing. Compared to the conventional STR workflow, which involves DNA extraction, purification, and elution volume reduction, the PE‐Swab direct STR amplification workflow does not require sample preparation and takes <60 sec before a touch sample is ready for STR amplification. Because there is no DNA loss due to sample preparation, the PE‐Swab workflow is more sensitive than the conventional STR workflow. The average peak height per sample obtained by the PE‐swab workflow is 3 times higher than that from the conventional workflow with both low‐level single source and two‐contributor mixture samples tested in this study.  相似文献   

9.
Abstract: Current profiling of rough diamond source is performed using different physical and/or morphological techniques that require strong knowledge and experience in the field. More recently, chemical impurities have been used to discriminate diamond source and with the advance of laser ablation–inductively coupled plasma–mass spectrometry (LA‐ICP‐MS) empirical profiling of rough diamonds is possible to some extent. In this study, we present a LA‐ICP‐MS methodology that we developed for analyzing ultra‐trace element impurities in rough diamond for origin determination (“profiling”). Diamonds from two sources were analyzed by LA‐ICP‐MS and were statistically classified by accepted methods. For the two diamond populations analyzed in this study, binomial logistic regression produced a better overall correct classification than linear discriminant analysis. The results suggest that an anticipated matrix match reference material would improve the robustness of our methodology for forensic applications.  相似文献   

10.
Recently, medical examiners reported two cases of a 21‐year‐old male and 24‐year‐old male with high amounts of morphine in their blood at autopsy. It was suspected that the decedents ingested lethal amounts of morphine from home‐brewed poppy seed tea. No studies to date have investigated opium alkaloid content extracted from poppy seeds by home‐brewing methods. Various poppy seed products were purchased from online sources and extracted with four home‐brewing methods representative of recipes found on drug user forums. Morphine, codeine, and thebaine were quantified in the tea extracts by liquid chromatography‐tandem mass spectrometry using a validated analytical method. Morphine, codeine, and thebaine concentrations from seeds were <1–2788 mg/kg, <1–247.6 mg/kg, and <1–124 mg/kg, respectively. Alkaloid yield varied between extractions, but regardless of extraction conditions, lethal amounts of morphine can be rinsed from poppy seed coats by home‐brewing methods.  相似文献   

11.
This study evaluated the extent to which divorce creates the “divided world of the child,” as well as consequences of this “divided world” for long‐term adjustment. An ethnically diverse sample of 1,375 young‐adult university students completed retrospective measures of parental nurturance and involvement, and current measures of psychosocial adjustment and troubled ruminations about parents. Results indicated that reports of maternal and paternal nurturance and involvement were closely related in intact families but uncorrelated in divorced families. Across family forms, the total amount of nurturance or involvement received was positively associated with self‐esteem, purpose in life, life satisfaction, friendship quality and satisfaction, and academic performance; and negatively related to distress, romantic relationship problems, and troubled ruminations about parents. Mother‐father differences in nurturance and involvement showed a largely opposite set of relationships. Implications for family court practices are discussed.  相似文献   

12.
Scholars have long argued that delinquency is a group phenomenon. Even so, minimal research exists on the nature, structure, and process of co‐offending. This investigation focuses on a particular void, namely the stability of 1) co‐offending and 2) co‐offender selection over time, for which divergent theoretical expectations currently exist that bear on issues central to general and developmental/life‐course theories of crime. By relying on individual‐level, longitudinal data for a sample of juvenile offenders from Philadelphia, we find that distinct trajectories of co‐offending exist over the course of the juvenile criminal career. This inquiry also develops an individualized measure of co‐offender stability, which reveals that delinquents generally tend not to “reuse” co‐offenders, although frequent offenders show a greater propensity to do so. The discussion considers the theoretical and policy implications of these findings as well as provides some avenues for future research.  相似文献   

13.
Mul‐T‐Lock is a high security lock cylinder distinguished by the use of a telescoping “pin‐in‐pin”—tumbler design. Picking the Mul‐T‐Lock cylinder with a traditional picking tool is highly complicated because it can get stuck between the inner and outer pins. The H&M Mul‐T‐Lock picking tool was designed to overcome this problem and facilitate the picking of the “pin‐in‐pin” cylinder. The purpose of this research is to determine whether H&M Mul‐T‐Lock picking tool leaves class characteristic mark and whether it can be distinguished from traditional picking tools marks and from regular key marks. It also describes and determines the class characteristic mark left on telescopic pins, its origin, recurrence, and its benefit to the toolmarks examiner. When receiving a Mul‐T‐Lock from a crime scene, a toolmarks examiner can quickly determine whether or not it was picked by an H&M Mul‐T‐Lock picking tool by noticing the class characteristic mark which this typical tool leaves.  相似文献   

14.
本文采用Seppak C_(18)小柱固相萃取鸦片中的五种主要成分,以反相高效液相色谱法,甲醇—甲酸—三乙胺水(35:1.5:0.5:63)为流动相,检验五种成分,各成分均有良好的回收率。方法简单、快速、准确。  相似文献   

15.
The “Blue Whale Challenge” is a dangerous Internet phenomenon. As per media reports, it involves a series of life‐threatening tasks imposed by a “curator” to “players,” who must fulfill the whole list, and it ends with the suicide of the player. The authors report the data of five suspected cases of “Blue Whales” managed from January 2016 to December 2017 by the staff of a unit (the “Bambi Unit” of the Pediatric Hospital “Regina Margherita” of Turin, Italy) that is dedicated to the evaluation of suspected abused children. Then, they analyzed this data in the light of the literature regarding self‐harm. This comparison highlights the role of the Internet in the spreading of self‐harm behavior among vulnerable adolescents who are characterized by epidemiological, psychological, psychiatric, social, and cultural risk factors. In conclusion, the authors suggest a multidisciplinary and specialized approach in the evaluation of adolescents who committed self‐harm activities.  相似文献   

16.
Optimisation and harmonisation of analytical and statistical methodology have been carried out between two forensic laboratories (Lausanne, CH and Lyon, F) in order to provide drug intelligence for cross-border cocaine seizures. The aim was to improve the gas chromatographic analysis of cocaine samples for profiling. Some important validation parameters were tested to verify the developed method and demonstrate its profiling capacity: the selectivity of the method with retention time reproducibility, the choice of a derivatisation agent improving the chromatography (MSTFA, BSA, TMSI and BSTFA+TMCS 1%), the cutting agents influence (matrix effect), the influence of the sample storage conditions and the sample quantity to weigh for analyses. Eight main alkaloids, which represent the sample signature, have been selected: ecgonine methyl ester, ecgonine, tropacocaine, benzoylecgonine, norcocaine, cis- and trans-cinnamoylcocaine and 3,4,5-trimethoxycocaine. Their stability in the solvent used (CHCl(3)/pyridine) was demonstrated. In order to reach the final objective, which is the comparison of samples seized and analyzed in two different laboratories, the harmonisation of the profiling method between the two laboratories had to be ensured and is the subject of ongoing research.  相似文献   

17.
We report a case of fatal intoxication from 1,4‐butanediol (1,4‐BD), which was ingested by a young and “naïve” gamma‐hydroxybutyrate (GHB) consumer during a party with the co‐ingestion of alcohol, cannabis, and methylene‐dioxy‐methamphetamine. The following drug concentrations were found using gas chromatography coupled with mass spectrometry on autopsy samples and on a cup and a glass found at the scene: 20,350 mg/L (bottle) for 1,4‐BD; 1020 mg/L (femoral blood), 3380 mg/L (cardiac blood), 47,280 mg/L (gastric content), and 570 mg/L (vitreous humor) for GHB. The concentration of GHB is difficult to interpret in forensic cases due to the possibility of an endogenous production of GHB. The variable tolerance of the user may also modify the peri‐ and postmortem GHB concentrations. This case underscores the need to have many different sources of toxicology samples analyzed to avoid the hypothesis of endogenous production of GHB.  相似文献   

18.
This article provides an in‐depth assessment of lone actor terrorists’ attack planning and preparation. A codebook of 198 variables related to different aspects of pre‐attack behavior is applied to a sample of 55 lone actor terrorists. Data were drawn from open‐source materials and complemented where possible with primary sources. Most lone actors are not highly lethal or surreptitious attackers. They are generally poor at maintaining operational security, leak their motivations and capabilities in numerous ways, and generally do so months and even years before an attack. Moreover, the “loneness” thought to define this type of terrorism is generally absent; most lone actors uphold social ties that are crucial to their adoption and maintenance of the motivation and capability to commit terrorist violence. The results offer concrete input for those working to detect and prevent this form of terrorism and argue for a re‐evaluation of the “lone actor” concept.  相似文献   

19.
A 20‐year‐old man, a cocaine addict and regular ecstasy user, with a medical history of allergic asthma died after ingesting half a tablet earlier the same day. The white tablet, stamped with a “smiling sun” logo looked very much like an ecstasy tablet and was sold as such. He experienced a severe asthma attack just after ingesting the half tablet and it evolved over the next few hours into fatal cardiorespiratory arrest. Biological samples, taken after embalming, were analyzed by high‐performance liquid chromatography tandem mass spectrometry (HPLC‐MS/MS). Analysis revealed meta‐chlorophenylpiperazine (mCPP) in concentrations of 45.8 mg in a similar tablet obtained later from the drug dealer, 5.1 ng/mL in the bile, 0.3 ng/g in the liver, 15.0 ng/mL in the urine, and its absence in a hair sample (<0.02 ng/mg), which indicated he was not a regular user (whereas strong concentrations of MDMA and cocaine were found in the hair). Interrogated by the police after his arrest, the dealer said that he had sold the victim and for the very first time two tablets with the same “smiling sun” logo. The tablet used for analysis was from the same brand as the one ingested by the victim. The autopsy excluded other causes of death, while the histological analyses showed a large number of polynuclear eosinophils in the bronchial walls, confirming the asthmatic pathology. None of the other organs examined (larynx, liver, heart, adrenal glands, and kidneys) showed any distinctive signs, and in particular no inflammatory infiltrate. The death was the result of an asthma attack in an asthmatic person, violently decompensated following ingestion of approximately 20 mg of mCPP.  相似文献   

20.
Reticuline (a precursor of opium alkaloids) was detected and characterised as its trimethylsilyl ethers, acetyl esters and methyl ethers by GC–EIMS and GC–CIMS in opium and the urine of opium users after hydrolysis by acid or β-glucuronidase as coextractive of morphine. Because this compound cannot be detected in heroin and poppy seeds, it is suggested as a differentiating marker between opium and heroin use, opium and poppy seeds use, or opium and “pharmaceutical” codeine use in cases when opiate use has been confirmed by detection of morphine and codeine in the urine. As well as being a constituent of opium, reticuline in the urine of opium users may also result from the metabolic demethylation of the three other benzyltetrahydroisoquinoline opium alkaloids: codamine, laudanosine and laudanine.  相似文献   

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