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1.
Abstract: The proper identification of illicit plants such as Papaver somniferum L (opium poppy) is important for law enforcement agencies. The identification of opium poppy was presently tested using 10 genetic markers that are universal for all plants or specific to a few poppy plants. The genetic distances of universal markers such as nuclear internal transcribed spacer (ITS), 18S rRNA, plastid rbcL, and trnL‐trnF intergenic spacer (IGS) of 14 species included in the Papaveraceae and Fumariaceae family were acquired by sequence comparisons. Both the ITS region and trnL‐trnF IGS showed high levels of interspecific divergence. Six Papaver genera‐specific markers were developed from coding regions involved in morphine biosynthesis. Three markers (TYDC, NCS, and BBE) produced amplicons only in opium poppy, providing a presence/absence test for opium poppy, while three additional markers (CYP80B1, SAT, and COR) were genus specific. These 10 markers might be useful for the forensic DNA analysis of opium poppy.  相似文献   

2.
The unambiguous identification of illicit substances, including Cannabis sativa, is a major concern of law enforcement agencies. Current methods of cannabis identification involve the use of techniques such as HPLC and GC to identify cannabinoids. A method for the identification of cannabis using DNA-specific primers has been developed and is described here. The nucleotide sequences between the trnL and trnF genes in the chloroplast of Cannabis sativa have been determined and Cannabis sativa-specific nucleotide sequences within the intergenic spacer between the trnL 3′ exon and trnF gene identified. Primers, made to these sequences, have been tested on a range of different plant extracts but only give a PCR product in the presence of Cannabis sativa. The successful production of a PCR product using these primers identifies the presence of cannabis.  相似文献   

3.
A general toxicology unknown case is presented to demonstrate our systematic approach. A 20-year-old male was found dead with multiple suicide notes. Overdose was suspected but substances were not known. Blood alcohol was negative. Urine was analyzed by enzyme-multiplied immunoassay technique and was negative for all drugs assayed. Urine was then extracted with ethyl acetate:hexane (1:1) at pH 10 and back-extracted into 1.0N sulfuric acid. The acidic layer was adjusted to pH 10, and re-extracted with ethyl acetate:hexane (1:1). The residue was analyzed by gas chromatography (GC) on a 3% OV-101 column. It was found to be negative for all commonly screened substances. However, several unknown peaks were observed. Electron impact mass spectra of these unknown peaks were obtained and searched for in our computer library of more than 25000 mass spectra. These unknown peaks were identified as doxylamine and pyrilamine by gas chromatography/mass spectrometry. The base peak and molecular ion for pyrilamine were at m/z 121 and 285, respectively. The base peak for doxylamine was at m/z 58. No molecular ion was observed for doxylamine. Both doxylamine and pyrilamine are antihistamines, but are promoted and used in the management of insomnia. Quantitation was performed on a GC using dexbrompheniramine as an internal standard. Blood concentrations for doxylamine and pyrilamine were 0.7 and 7.0 mg/L, respectively. Concentrations in other tissues were determined. Death was caused by combined doxylamine and pyrilamine intoxication; the manner of death was suicide.  相似文献   

4.
5.
Abstract: When rope is found at a crime scene, the type of fiber is currently identified through its microscopic characteristics. However, these characteristics may not always unambiguously distinguish some types of rope from others. If rope samples contain cells from the plants of origin, then DNA analysis may prove to be a better way to identify the type of rope obtained from a crime scene. The objective of this project was to develop techniques of DNA analysis that can be used to differentiate between ropes made from Cannabis sativa L. (hemp), Agave sisalana Perrine (sisal), Musa textilis Née (abaca, “Manila hemp”), Linum usitatissimum L. (flax), and Corchorus olitorus L. (jute). The procedures included extracting the DNA from the rope, performing polymerase chain reaction (PCR) using the extracted DNA as a template, and analyzing the DNA products. A primer pair for PCR, chosen from within a chloroplast gene for the large subunit of ribulose bisphosphate carboxylase/oxygenase, was designed to be specific for plant DNA and complementary to the genes from all five plants. The resulting PCR fragments were approximately 771 base pairs long. The PCR fragments, distinguished through base sequence analysis or restriction enzyme analysis, could be used to identify the five different rope types. The procedure provides a useful addition to visual methods of comparing rope samples.  相似文献   

6.
Abstract: The Quantifiler® Duo DNA Quantification kit enables simultaneous quantification of human DNA and human male DNA as well as detection of inhibitors of PCR in a single real-time PCR well. Pooled human male genomic DNA is used to generate standard curves for both human (ribonuclease P RNA component H1) and human male (sex determining region Y) specific targets. A shift in the cycle threshold (CT) values for the internal positive control monitors the presence of PCR inhibitors in a sample. The assay is human specific and exhibits a high dynamic range from 0.023 to 50 ng/μL. In addition, the multiplex assay can detect as little as 25 pg/μL of human male DNA in the presence of a 1000-fold excess of human female DNA. The multiplex assay provides assessment of the DNA extract and guidance for the selection of the appropriate AmpFℓSTR® Amplification Kit to obtain interpretable short tandem repeat profiles.  相似文献   

7.
Nicotine is a potent neurotoxin alkaloid and is used in e‐cigarette liquid. The LC/MS/MS method was linear over 0.01–1.0 mg/L (r2 = 0.992–0.995). Limit of detection and limit of quantitation were 0.001 mg/L (S/N = 3) and 0.003 (S/N = 10). The inaccuracy and imprecision were <13.2%. The recoveries were >99.3%. A 39‐year‐old dentist was found dead lying on the floor under the couch in his dental clinic. The concentration of nicotine, cotinine, and trans‐3′‐hydroxycotinine (heart blood/peripheral blood) was analyzed as follows: 87.2/85.2 mg/L (ratio 1.0), 1.4/1.1 mg/L (ratio 1.3), and 0.012/0.0089 mg/L (ratio 1.3), respectively. The concentration of nicotine was determined to be 6734.8 mg/kg in gastric contents and 7262.0 mg/L in remaining e‐liquid. Only, high concentration of nicotine was detected in the gastric contents as well as the two pieces of evidence collected from the death scene. This fatal case resulted from oral ingestion of e‐cigarette liquid. It is estimated that at least 714 mg of nicotine was orally ingested.  相似文献   

8.
A pesticide poisoning victim suspected initially as having died a natural death was autopsied. The victim was a 47-year-old male. Macroscopically, signs of acute death and, in particular, general erosion in the mucosa of the airways and esophagus were observed. In the gastric contents, which had a pungent smell and a greenish-brown color, 5.00 g/L of propanil, 1.27 g/L of carbaryl, 0.38 g/L of ethylbenzene, and 0.32 g/L of xylene were detected. In the blood (serum), 21.6 mg/L of propanil, 8.1 mg/L of carbaryl, 1.7 mg/L of ethylbenzene, and 4.0 mg/L of xylene were identified. Postmortem methemoglobinemia (45%) was recognized. The cause of death was considered to have been pesticide poisoning; propanil was probably most responsible for his death. The police considered the case to be "death with illness as the suspected cause." By performing an autopsy, however, we were able to clarify that the cause of death was pesticide poisoning.  相似文献   

9.
The Philadelphia Medical Examiners Office has reported a series of 15 deaths between February 1999 and June 2005 of infants and toddlers 16 months and younger in which drugs commonly found in over-the-counter (OTC) cold medications were present. A total of 10 different drugs were detected: pseudoephedrine, dextromethorphan, acetaminophen, brompheniramine, carbinoxamine, chlorpheniramine, ethanol, doxylamine and the anticonvulsants, phenobarbital, and phenytoin. The drugs were confirmed and quantified by gas chromatography (GC)-mass spectrometry, with the exception of ethanol, which was analyzed by headspace GC and of phenobarbital and phenytoin that were quantified by GC with a nitrogen phosphorus detector. The most predominant drug was pseudoephedrine, which was found in all of the cases (blood concentration, n=14, range=0.10-17.0 mg/L, mean=3.34 mg/L) and was the sole drug detected in three cases. Acetaminophen was detected in blood from each of the five cases with sufficient sample. Other drugs (with frequency of detection) were dextromethorphan (five cases), carbinoxamine (four cases), chlorpheniramine (two cases) and brompheniramine, doxylamine, and ethanol (one case each). In the majority of the cases, toxicity from drugs found in easily available OTC medications was listed either as the direct cause of death or as a contributory factor. The manner of death was determined to be natural in only two of the cases. This postmortem study supports previous evidence that the administration of OTC cold medications to infants may, under some circumstances, be an unsafe practice and in some cases may even be fatal. The treating physicians and the general public need to be made more aware of the dangers of using OTC cold medications to treat very young children so that these types of tragedies might be avoided.  相似文献   

10.
Abstract: Murder–suicide is a relatively uncommon event but as reported by the New York Times, it has occurred and continues to occur yearly. Previous research has indicated that those who commit murder–suicides tend to be men, are in or have been in an intimate relationship with the victim, victims tend to be women, and a firearm is most likely to be used. This study uses a newspaper surveillance methodology to examine such cases. Articles from the New York Times as found in the New York Times Index were coded, analyzed, and examined. The cases, 166 in total, support the findings from prior research. The trend data was examined by cross tabulations and chi‐square analysis. The findings suggest that murder–suicides are rare events and when they occur they usually involve a male perpetrator and an intimate partner victim who is either a wife or girlfriend with the event occurring in a private home. A firearm is the most commonly used method for both murders and suicides, particularly if there was more than one murder victim. The authors conclude by suggesting that future research should focus on using the forthcoming data resource in the CDC’s National Violent Death Reporting System (NVDRS) to examine the occurrence of murder–suicide.  相似文献   

11.
Abstract: Little is known about the racial patterns of crimes committed by sexual homicide offenders (SHOs). This study examined race and age influences on victim–offender relationship for juvenile and adult SHOs. A large sample (N = 3868) from the Supplemental Homicide Reports (1976–2005) was used. Analyses of victim–offender patterns included examining victim age effects (child, adolescent, adult, and elderly). The findings revealed several race‐ and age‐based differences. Black offenders were significantly overrepresented in the SHO population. This finding held for juveniles and adults independently. White SHOs were highly likely to kill within their race, “intra‐racially” (range 91–100%) across four victim age categories, whereas Black SHOs killed both intra‐racially (range 24–82%) and inter‐racially (18–76%), with the likelihood of their killing inter‐racially increasing as the age of the victim increased. This study underscores the importance of considering victim–offender racial patterns in sexual murder investigations, and it offers practical implications for offender profiling.  相似文献   

12.
How victims are portrayed in fictional crime dramas is an important way that individuals come to understand and interpret what it means to be a victim of crime. We examine how demographic variables (e.g., gender, race, age), incident variables (e.g., location of offense, relationship between victim and offender, type of crime), and behavioral variables (e.g., drug use/alcohol use, sexual promiscuity, negative personality traits, or concealing elements of personality) predict victim blame. Although some literature has analyzed victims in fictional crime dramas, such literature has been limited to a single year, a single show, a particular crime, or a particular factor. We extend this literature by focusing on multiple factors that predict victim blame using data collected from a systematic sample of 124 episodes from 4 fictional crime dramas (CSI, Law & Order: Special Victims Unit, Criminal Minds, and Without a Trace) over 7 years (2003–2010).  相似文献   

13.
This study reports on the comparison of a standard extraction process with the direct PCR approach of processing low-level DNA swabs typical in forensic investigations. Varying concentrations of control DNA were deposited onto three commonly encountered substrates, brass, plastic, and glass, left to dry, and swabbed using premoistened DNA-free nylon FLOQswabs. Swabs (= 90) were either processed using the DNA IQ kit or, for direct PCR, swab fibers (~2 mm2) were added directly to the PCR with no prior extraction. A significant increase in the height of the alleles (< 0.005) was observed when using the direct PCR approach over the extraction methodology when controlling for surface type and mass of DNA deposited. The findings indicate the potential use of direct PCR for increasing the PCR product obtained from low-template DNA samples in addition to minimizing contamination and saving resources.  相似文献   

14.
As part of a suspected homicide investigation, a sampling of the gastric contents from the victim was forwarded to the U.S. Food and Drug Administration's Forensic Chemistry Center (FCC) for analysis of specific, selected components. The victim was known to have consumed string mozzarella cheese, as a snack, less than 24 h before his disappearance and the subsequent discovery of the body. The investigation sought to confirm or dismiss speculation the victim may have been fed a meal or eaten additional food prior to his death. Analysis of the stomach contents involved examination by stereoscopic light microscopy (SLM) and isolation, processing, and analysis of suspect materials by scanning electron microscopy (SEM). Several wax-like, off-white to cream-colored objects were noted by SLM examination and removed from the gastric contents. Through a series of fixation, sectioning, drying, and coating steps, these objects were prepared for analysis by SEM. Comparison of the suspect material with laboratory control string mozzarella cheese showed excellent correlation between the analyzed samples, confirming the suspect material from the stomach contents as string mozzarella cheese.  相似文献   

15.
Unintended compounds produced by inexperienced clandestine chemists may present a challenge in laboratories tasked with their identification. In March 2020, an anonymously submitted tablet purchased as a generic form of Xanax was analyzed by Erowid's DrugsData.org . The gas chromatography–mass spectrometry (GC–MS) results publicly released online indicated several unidentified compounds due to a lack of database references at that time. Elucidation by our group indicated the presence of several structurally related compounds that were linked to a failed synthesis of alprazolam. For this case study, a published procedure for the synthesis of alprazolam starting with the chloroacetylation of 2-amino-5-chlorobenzophenone was identified as a potential source of this failure. The procedure was reproduced to identify pitfalls of the methodology and examine its possible link to the illicit tablet. Reaction outcomes were analyzed via GC–MS and compared to the tablet submission data. The major compound in this submission, N-(2-benzoyl-4-chlorophenyl)-2-chloroacetamide, along with several related byproducts were successfully reproduced indicating that the tablet contents potentially stem from a failure to synthesize alprazolam.  相似文献   

16.
Researchers have studied the involvement of drugs and alcohol in fatal road traffic incidents, but with particular emphasis on the possible impairment of the driver. This paper describes a comparative study of drug and alcohol findings in various victim groups (drivers of cars, vans or lorries, car passengers, motorcyclists, motorcycle passengers, cyclists and pedestrians) between 2000 and 2006. Post-mortem blood and urine specimens submitted were analysed by immunoassay, GC–NPD, GC–FID, GC–MS and HPLC–DAD. The results of 1047 cases indicated 54% of all victims were positive for drugs and/or alcohol, with the highest percentage of positive findings occurring in pedestrians (63%). Males between the ages of 17–24 were most likely to be involved in a road traffic accident, whether being in control of a vehicle (driver) or involved indirectly (car passenger, pedestrian, motorcycle passenger). A wide range of drugs were detected (e.g. drugs of abuse, anti-convulsants, anti-histamines, anti-inflammatories, anti-psychotics, cardiac drugs and over-the-counter products), but alcohol and cannabinoids were the most frequent substances across the victim groups. When detected, alcohol was commonly above the legal driving limit in blood and urine (> 63% in those in control and > 60% not in control). Overall, the presence of drugs and/or alcohol was of similar frequency in those victims in control (55% of driver, 48% of motorcyclists, 33% of cyclists) and not in control of a vehicle (52% of car passengers, 63% of pedestrians). This degree of frequency strongly implicates the involvement of drugs and alcohol in road traffic incidents and infers an effect on driving ability and individual impairment.  相似文献   

17.
Importance of forensic entomology becomes inevitable when come across some incident where corpse is unidentifiable and lot of maggots or other insects are present. The most common application of forensic entomology is to use insects for the identification of specimens or human remains. DNA analysis recovered from a larva's gut contents can be used to identify a missing body. The obtained human STR and SNP profile support the association of a maggot to a specific patients or corpse. Main aim of this research was the identification of human DNA from gut contents of third instar maggots (larvae of Lucilia sericata) placed on diabetic patient's wounds for treatment purpose. Maggots (8–15) were taken from each diabetic patients (no. of the patients 8) and DNA was extracted from the gut contents manually by using Qiagen tissue protocol. Agarose gel electrophoresis was performed and the total size of DNA was seen using UV transilluminator. PCR amplification, STRs and SNPs profiling was then performed using PCR 9700 and AmpFLSTR Identifiler and SnaPshot Multiplex Kit (Applied Biosystems) respectively. The results were analyzed on ABI 310. SNP profiles were good and identifiable compared to the STRs where amplification was poor and the peaks were low. This may be the fact of the enzymatic activity present in the gut of the larvae which cause tremendous reduction in DNA size and thus yield. The results of this study reveals that it is possible to obtain a complete human profile using STRs and SNPs even if DNA is recovered from gut contents of maggots.  相似文献   

18.
Abstract: The PrepFiler? Forensic DNA Extraction Kit enables isolation of genomic DNA from a variety of biological samples. The kit facilitates reversible binding of DNA with magnetic particles resulting in high DNA recovery from samples with very low and high quantities of biological materials: 0.1 and 40 μL of human blood (donor 2) provided 14 and 2883 ng of DNA, respectively. Following the revised SWGDAM guidelines, performance of the developed method was investigated using different sample types including saliva on swabs, semen stains on cotton fabric, samples exposed to environment, samples with polymerase chain reaction (PCR) inhibitors, blood stains (on denim, cotton cloth, and FTA® paper), and touch evidence‐type samples. DNA yields for all samples tested were equal or better than those obtained by both phenol–chloroform extraction and commercial kits tested. DNA obtained from these samples was free of detectable PCR inhibitors. Short tandem repeat profiles were complete, conclusive, and devoid of PCR artifacts.  相似文献   

19.
Although numerous studies have found a strong relationship between offending and victimization risk, the etiology of this relationship is not well understood. Largely absent from this research is an explicit focus on neighborhood processes. However, theoretical work found in the subculture of violence literature implies that neighborhood street culture may help to account for the etiology of this phenomenon. Specifically, we should expect the magnitude of the victim–offender overlap to vary closely with neighborhood‐based violent conduct norms. This research uses waves 1 and 2 of the Family and Community Health Study (FACHS) to test the empirical validity of these notions. Our results show that the victim–offender overlap is not generalizeable across neighborhood contexts; in fact, it is especially strong in neighborhoods where the street culture predominates, whereas it is significantly weaker in areas where this culture is less prominent. These results indicate that neighborhood‐level cultural processes help to explain the victim–offender overlap, and they may cause this phenomenon to be context specific.  相似文献   

20.
Negative observer reactions towards victims may be related to people’s expectations of the characteristics and demeanor of an ideal victim. We examined how expressed emotion, victim sex, and type of victimization influence observers’ perceptions of victim credibility, victim character, and harm. Our hypothesis was that angry victims, male victims, and victims of sexual violence are perceived less positively than sad victims, female victims, and victims of physical violence. Additionally, we anticipated that expectancy violations following expressed agentic/high status, or passive/low-status emotions of the victim would lead to negative reactions. Participants (N?=?335) read a written victim impact statement, by a male or female victim of a sexual or physical assault, in which anger or sadness was expressed. The results show that observers generally respond more negatively to male victims than to female victims, and to victims expressing anger rather than sadness. However, a two-way interaction between expressed emotion and type of crime revealed that expressed emotion only significantly influences character derogation and victim credibility in cases of physical violence. Finally, emotion expectancy violations based on ex-ante expectations lead to derogation and diminished credibility. The discussion focuses on how emotion expectancy violations seem intimately tied to stereotype-ridden features of victimization.  相似文献   

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