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71.
The National Forensic Laboratory Information System (NFLIS) is a drug surveillance program of the US Drug Enforcement Administration that systematically collects data on drugs that are seized by law enforcement and submitted to and analyzed by the Nation's forensic laboratories (NFLIS-Drug). NFLIS-Drug data are increasingly used in predictive modeling and drug surveillance to examine drug availability patterns. Given the complexity of the data and data collection, there are some common methodological pitfalls that we highlight with the aim of helping researchers avoid these concerns. The analysis done for this Technical Note is based on a review of the scientific literature that includes 428 unique, refereed article citations in 182 distinct journals published between January 1, 2005, and April 30, 2021. Each article was analyzed according to how NFLIS-Drug data were mentioned and whether NFLIS-Drug data were included. A sample of 37 articles was studied in-depth, and data issues were summarized. Using examples from the literature, this Technical Note highlights eight broad concerns that have important implications for the proper applications, interpretations, and limitations of NFLIS-Drug data with suggestions for improving research methods and accurate reporting of forensic drug data. NFLIS-Drug data are timely and provide key information to inform drug use trends across the United States; however, our present analysis shows that NFLIS-Drug data are misunderstood and represented in the literature. In addition to highlighting these issues, DEA has created several resources to assist NFLIS data users and researchers, which are summarized in the discussion.  相似文献   
72.
File‐sharing apps with Wi‐Fi hotspot or Wi‐Fi Direct functions become more popular. They can work on multiple platforms and allow users to transfer files in a concealed manner. However, when criminals use these apps in illegal activities, it becomes an important issue for investigators to find digital evidence on multiple platforms. At present, there are few studies on this topic, and most of them are limited to the single platform problem. In this paper, we propose a forensic examination method for four popular cross‐platform file‐sharing apps with Wi‐Fi hotspot and Wi‐Fi Direct functions: Zapya, SHAREit, Xender, and Feem. We use 22 static and live forensic tools for 11 platforms to acquire, analyze, and classify the forensic artifacts. In our experiments, we find many useful forensic artifacts and classify them into six categories. The experimental results can support law enforcement investigations of digital evidence and provide information for future studies on other cross‐platform file‐sharing apps.  相似文献   
73.
The analysis of cannabis plant material submitted to seized‐drug laboratories was significantly affected by the signing of the Agricultural Improvement Act of 2018, which defined hemp and removed it from the definition of marijuana in the Controlled Substances Act. As a result, field law enforcement personnel and forensic laboratories now are in need of implementing new protocols that can distinguish between marijuana‐type and hemp‐type cannabis. Colorimetric tests provide a cost‐effective and efficient manner to presumptively identify materials prior to submission to a laboratory for analysis. This work presents the validation of the 4‐aminophenol (4‐AP) color test and demonstrates its utility for discriminating between marijuana‐type and hemp‐type cannabis (i.e., typification). Validation studies included the testing of numerous cannabinoid reference materials, household herbs, previously characterized cannabis plant samples, and real‐case samples. The 4‐AP test reliably produces a pink result when the level of Δ9‐tetrahydrocannabinol (THC) is approximately three times lower than the level of cannabidiol (CBD). A blue result is generated when the level of THC is approximately three times higher than that of CBD. Inconclusive results are observed when the levels of THC and CBD are within a factor of three from each other, demonstrating the limitations of the test under those scenarios.  相似文献   
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The differentiation of inks on a questioned document can highlight a fraudulent insertion and is usually carried out by optical comparison and thin-layer chromatography (TLC). Laser desorption ionization mass spectrometry (LDI-MS) may also be used for the analysis of dyes from ink. This analytical technique was compared with a standard method of high-performance TLC (HPTLC) according to their capacity to differentiate blue ballpoint inks. Ink entries on paper from 31 blue ballpoint pens have been analyzed and their dye ink formulations compared. The pens were classified into 26 classes by LDI-MS against 18 for HPTLC. LDI-MS proved to be a more powerful method for differentiating ink formulations because it provides information about dye structures (molecular weights) and relative quantification of dye classes (peak areas). Sample preparation was minimal and analysis time was short in contrast to the more complex extraction, application, and development steps of the HPTLC method. However, only basic dyes and pigments were identified using positive mode LDI-MS, while HPTLC did yield additional information about acid dyes.  相似文献   
76.
In the practice of forensic handwriting experts, the size of the writing on a questioned document may be different from that of known samples. In this study, the hypothesis of shape invariance of handwritten closed loops across size increasing was tested. A Fourier methodology was applied to 2325 small letters (591 a loops, 547 d loops, 596 o loops and 591 q loops) and 692 enlarged letters (162 a loops, 173 d loops, 173 o loops and 184 q loops), in a population of 13 writers who were asked to write letters in their usual size and about three times larger. Most of the writers presented similar modifications when increasing the size of the loops; they produced enlarged loops significantly more round and less slanted towards the right or the left. Furthermore, a discrimination was demonstrated between the writers on the basis of the enlarged loops, with a correct classification rate superior to 90%, whatever the letter (a, d, o or q). A classification of the enlarged loops in their corresponding writer was then possible. On the contrary, when comparing the enlarged loops to the small ones, almost one half of the enlarged loops were allocated to a wrong writer. Shape invariance was thus not supported for this particular application. Consequently, when comparing documents with a different writing size, differences in loops shape should be interpreted cautiously because they may be due to a different writer, but they may also be due to an enlargement of the loops. Therefore, reference material of similar writing size to that of the questioned writing should be requested for the comparison of handwritten loops.  相似文献   
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The present study investigated 154 consecutive admissions to the Regional Treatment Center (Ontario) Sex Offender Treatment Program with reference to psychopathy and outcome. Ratings of treatment behavior, as well as clinical judgments as to whether risk was reduced, were coded based on treatment reports. With reference to Psychopathy Checklist-revised (PCL-R) scores, survival analyses indicated that high scorers recidivated at significantly higher rates than low scorers. However, offenders who received high PCL-R scores and lower scores on measures of treatment behavior recidivated at the same rate as low scorers on the PCL-R. Furthermore, among high PCL-R offenders, those rated as lower risk at post treatment in fact reoffended at a lower rate than those whose risk was rated as unchanged, although this difference failed to reach significance. Findings are discussed in light of the clinical and research literature.  相似文献   
79.
This study explored the effects of marital conflict and family structure on the self-concepts of youth aged 8–12. Subjects were 16 mother-youth pairs from intact parent families (IP) and 17 mother-youth pairs from separated parent families (SP). Results revealed youth in families with low marital hostility and high marital affection had significantly more positive self-concepts. Analyses suggested differences between IP and SP groups may best be explained by differences in marital hostility. The authors discuss the effects of marital discord on parenting within an ecosystems perspective.This study received partial support from the Indiana University School of Nursing Alumni Association and Sigma Theta Tau, Alpha Chapter.Research interests: children's social networks, marital structure, and parenting.Research interests: chronic illness in children.  相似文献   
80.
Literature on family drug treatment courts (FDTCs) suggests that parental participation in these courts is associated with improved substance abuse treatment and child welfare system outcomes. Despite these beneficial outcomes, FDTCs serve only 7‐10% of eligible child welfare involved families. As part of a FDTC evaluation, this FDTC site sought to provide stakeholders with information about costs and benefits. Considering the program costs alongside the cost avoidance from reduced time in foster care, this analysis determined that FDTC participation resulted in a net savings per child of $9,710. The cost component of the evaluation proved valuable, challenging, and informative.  相似文献   
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