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91.
The opioid epidemic, impacted from the proliferation of fentanyl, has added impetus to the need to detect fentanyl, sources of fentanyl, and places where fentanyl and drugs adulterated with fentanyl are available. Many darknet marketplaces (DNMs) have rules that ban fentanyl. However, it is unclear how these affect the fentanyl market. Using the AlphaBay DNM as a case study, we conducted mixed methods qualitative research. We scraped and analyzed data from the AlphaBay I2P website using, among other methods, content and social network analysis, to uncover hidden fentanyl networks. Our research highlights the next evolution of darknet marketplaces – the migration of DNMs from Tor to I2P and the methods that can be used identify fentanyl networks, irrespective of where sites are: I2P, Tor, or multihomed on I2P and Tor. Despite its ban in the Global AlphaBay Rules, our research revealed the sale of fentanyl on the AlphaBay DNM. Unlike previous studies, our findings predominantly revealed the covert sale of fentanyl on AlphaBay and predatory vendors selling illicit drugs, which unbeknownst to buyers, contained fentanyl. To a lesser extent, our findings identified the overt sale of fentanyl patches on AlphaBay. Although we examined only one DNM, the prevalence of the covert sale of fentanyl and the presence of predatory vendors underscores the importance of research that decodes the language of vendors who surreptitiously sell fentanyl or drugs adulterated with fentanyl or other illicit substances. The results of our research can inform strategies aimed at disrupting and dismantling DNM fentanyl networks.  相似文献   
92.
The recovery of identifiable fingerprints from fired cartridge cases is challenging. Therefore, the characterization of chemical modifications and their effects on fingerprint integrity post-firing is essential. In this study, the primary fingerprint lipids, including myristic acid, pentadecanoic acid, palmitoleic acid, palmitic acid, stearic acid, squalene, and cholesterol in fired and unfired cartridges, were extracted with acetonitrile, followed by derivatization using N,O-Bis(trimethylsilyl)trifluoroacetamide with 1% trimethylchlorosilane (BSTFA/1%TMCS). Squalane was used as the internal standard, and all quantifications were performed using gas chromatography coupled with mass spectrometry using a triple-quadrupole mass filter. All lipids identified in the unfired cartridges were also detected in the fired cartridges, and statistical analysis using Student's t-test and F tests was performed with a 95% confidence level. The concentration of lipids in the unfired cartridges was found to be similar to that detected in the fired cartridges, except for squalene, the recovery of which was 28% lower in the fired cartridges.  相似文献   
93.
The rise of fentanyl and fentanyl analogs in the drug supply pose serious threats to public health. Much of these compounds enter the United States through shipping routes. Here we provide a method for fentanyl screening and analysis that utilizes pressure-sensitive adhesive (PSA) lined paper to recover drug residues from parcel-related surfaces. The paper used is commercially available repositionable notes (also called post-it or sticky notes). From this paper, mass spectra were obtained by paper spray-mass spectrometry (PS-MS), where PSA paper served as both a sampling and analysis substrate. Seven fentanyl-related compounds were analyzed: fentanyl, 4-anilino-N-phenethylpiperidine (4-ANPP), N,1-diphenethyl-N-phenylpiperidin-4-amine (phenethyl-4-ANPP), valerylfentanyl, 4-fluoroisobutyrylfentanyl (4-FIBF), carfentanil, and p-fluorofentanyl. These compounds were recovered by PSA paper and identified by PS-MS from packaging tape and plastic at 50 ng and from cardboard and shipping labels at 100 ng. The impact of cutting agents on PS-MS analysis of fentanyl analogs was explored. No trends of analyte suppression were found at high concentrations of the cutting agents caffeine, diphenhydramine, and lidocaine when recovered from surfaces. A cartridge that required no precise cutting of PSA paper prior to sampling or analysis was evaluated for use in PS-MS for fentanyl screening. Recovery and detection of fentanyl from plastic sheeting was demonstrated with this cut-free cartridge. The cut-free cartridge showed somewhat less consistency and lower analyte signal than the standard cartridge, but performance was suitable for potential screening applications. In combining PSA surface sampling with PS-MS for drug screening, both sampling and detection of fentanyl-related compounds is simple, rapid, and low-cost.  相似文献   
94.
Forensic casework samples often include human hairs, teeth, and bones. Hairs with roots are routinely processed for DNA analysis, while rootless hairs are either not tested or processed using mitochondrial DNA. Bones and teeth are submitted for human remains identifications for missing persons and mass disaster cases. DNA extraction from these low templates and degraded samples is challenging. The new InnoXtract DNA extraction method utilizes magnetic beads that are optimized to bind small DNA fragments, as small as 100 base pairs, to purify high-yield DNA from compromised samples. This validation study evaluates InnoXtract's ability to obtain amplifiable DNA from samples such as rootless hairs and skeletal remains. Studies performed include sensitivity, stability, repeatability, reproducibility, non-probative samples, and comparison to standard organic extractions. Sensitivity studies demonstrate average yield recoveries ranging from 53% to 100% and 73% to 85% for the InnoXtract hair and bone methods, respectively. Studies demonstrate consistent results across a range of sample types, such as insulted and un-insulted bone and teeth, as well as hair shafts from donors of various ages, gender, race, and hair characteristics. The InnoXtract bone method outperformed organic extraction. The method was successfully automated on a MagMAX™ Express-96, with recoveries over 70% relative to the manual version. InnoXtract has the potential as an automated high-throughput, high-yield bone extraction method with 6 h of total extraction time for up to 96 samples. The validation study results demonstrate that the InnoXtract kits produce high-yield and high-quality DNA from compromised bone, teeth, and hair shaft samples.  相似文献   
95.
Ethanol stability in preserved antemortem blood has been widely studied since it is a common practice in cases involving suspected impaired driving to collect antemortem blood in evacuated blood tubes containing sodium fluoride. In some situations, antemortem blood is submitted to a forensic laboratory for ethanol analysis in evacuated blood tubes that contain only an anticoagulant. There has been limited research on ethanol stability in antemortem blood stored without a preservative. On two occasions, antemortem blood was collected from five ethanol-free individuals into 6-ml Vacutainer® tubes containing only 10.8 mg potassium EDTA. The blood tubes were spiked with ethanol to approximately either 0.08 or 0.15 g/dl. Dual-FID headspace gas chromatography was used to analyze 58 blood tubes, 29 from each session, for ethanol 1 day after sample collection and again after 1 year of refrigerated storage (~4°C). Statistically significant decreases in ethanol were detected at the 0.05 level of significance. Mean decreases in ethanol after 1 year of storage for the 0.08 and 0.15 g/dl samples were 0.013 and 0.010 g/dl, respectively. The mean ethanol decrease across all tubes was 0.012 g/dl. The range of decreases for the 58 blood tubes was 0.003–0.018 g/dl. The mean ethanol decreases measured in this unpreserved antemortem blood are comparable in magnitude to those previously observed in antemortem blood containing sodium fluoride after 1 year of refrigerated storage. Ethanol did not increase in the antemortem blood samples despite the absence of sodium fluoride.  相似文献   
96.
Optical tweezers have a wide range of uses for mechanical manipulation of objects in the microscopic range. This includes both living and static cells in a variety of biomedical and research applications. Single-focus optical tweezers, formed by focusing a laser beam through a high numerical aperture immersion objective, create a significant force, which enables controlled transport of a variety of different cell types and morphologies in three dimensions. Optical tweezers have been previously reported to capture and separate spermatozoa from a reconstituted simulated postcoital sample. We report herein the development of a simplified, more efficient cell transfer protocol that can separate and isolate both spermatozoa as well as leukocytes, with similar efficiencies as those previously reported. The new cell transfer method was used to separate sperm cells from a reconstituted mixture of spermatozoa and vaginal epithelial cells, with complete STR profiles developed from 50 cells with little evidence of contribution from the female contributor to the mixture. This modified protocol was then used to separate 21 samples of enriched leukocytes, with trapped cells ranging from 5 to 22 cells. Complete STR profiles were developed from as few as 10 leukocytes. Thus, with minimal sample preparation and a short trapping time, this method has the potential to provide an alternative to traditional differential extraction methods for separation of sperm:nonsperm mixtures while also providing versatility for separation of cells with differing morphologies.  相似文献   
97.
98.
Among the wide range of theories explaining why some people vote and others do not, one is recently gaining particular popularity. This is the theory of voting as a habit (e.g. Plutzer, 2002; Franklin, 2004; Hooghe, 2004). The empirical evidence supporting this theory covers only Western democracies, so the following question might be asked: is this pattern universal? In the case of old democracies, voting is a habit acquired gradually in a process which starts at the moment of the very first election one can cast the ballot. In new democracies the situation is different, as we can pinpoint the starting moment (first democratic election), which is the same for different voters and thus different age cohorts. In this paper we investigate voting as a habit in new democracies, using data from the Polish National Election Study. We find that voting in Poland has some habitual aspect; repeated voting brings about a (sort of) habit, which has an intrinsic, irreducible effect on voter turnout. We also find that habit of voting is formed likewise in all age cohorts.  相似文献   
99.
This paper examines how The Gangster of Love (1996), the second novel by Filipino American artist and writer Jessica Hagedorn, dismantles ready-made assumptions about the construction of minority and mainstream cultures. Spanning the period from the 1970s to the early 1990s, Gangster depicts the life of Rocky Rivera, a Filipina American young artist. As it portrays Rocky's family and friends, the novel examines the drastic re-articulation of the US’s self-image brought about by Filipino Americans and other groups marginalized as minorities by virtue of their ethnic, socio-cultural, and/or sexual identities. The narrative challenges dominant notions of who and what makes history, juxtaposing historical references with fictionalizations of real episodes and completely fictional incidents, and making a constant use of parody, irony, jokes and clichés. This paper studies Rocky's reworks of her multiple ethnic and socio-cultural allegiances in connection with her passion for music and popular culture, placing these reworks in the context of the Philippines’ colonial and neo-colonial background and multi-cultural US history. It also considers succinctly how Gangster's postcolonial dimensions intersect with a feminist and postmodern consciousness in a gendered strategy of socio-cultural resistance and critique.  相似文献   
100.
A fast method was designed for the simultaneous determination of amphetamine (A), methamphetamine (MA), PMA, MDA, MDMA, MDEA and MBDB in urine. The drugs were analysed by LC (ESI)-MS/MS, after a simple liquid-liquid extraction in the presence of the deuterated analogues. Reverse phase separation on an Atlantis dC18 Intelligent Speed column was achieved in less than 4 min under gradient conditions, and the total run time was 8 min. The method was fully validated, including linearity (1-1000 ng/mL for A, MDMA, MDEA and MBDB; 2-1000 ng/mL for MDA and PMA; 1-200 ng/mL for MA; r2>0.99 for all compounds), recovery (>80%), within-day and between-day precision and accuracy (CV and MRE<12.7% for intermediate level and ULOQ, and <17.2% for LLOQ), limit of detection (0.2 ng/mL for MDMA, MDEA and MBDB; 0.5 ng/mL for A, MA and PMA; 1 ng/mL for MDA) and quantitation (1 ng/mL for A, MA, MDMA, MDEA and MBDB; 2 ng/mL for MDA and PMA) and relative ion intensities. No matrix effect was observed. The procedure proved to be sensitive, specific and rapid, and was applied to real forensic cases.  相似文献   
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