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101.
Robotic waste management automation systems are increasingly utilized around the globe as a user-friendly, ecological and hygienic alternative to waste disposal, simultaneously reducing the volume and frequency of waste collection. The present paper aims to report a case of death by compaction in an automated robotic waste management system and review relevant literature on compactor-related fatalities. The unusual fatal accident involved a 37-year-old male citizen who deliberately entered the robotic dumpster to retrieve his accidentally discarded medication. Upon entering the robotic chamber, the compaction system was automatically activated, although all safety measures were in full operation. This paper highlights the lack of standardized reporting on compactor-related mortality, which however is of importance both in terms of its social impact and public safety. These deaths occur rarely, in scattered areas of the globe, associated with various situations (e.g., occupational fatalities, homeless people, infanticide) and trash compactors of different types, technology, age, maintenance quality, warning signage and safety interlocks. In all previously reported fatalities, the technology involved was considerably older (as in conventional waste containers, garbage compaction trucks, chute-fed compactors in buildings, etc.). The case described in the present report is a rare event in both literature and international news coverage as it encompasses a fully automated technology intended for unsupervised, direct use by the public being located in public spaces where all citizens can interact with it. The aim of this report is to raise awareness and improve knowledge about safety parameters so that similar incidents can be avoided in the future.  相似文献   
102.
Forensically relevant single nucleotide polymorphisms (SNPs) can provide valuable supplemental information to short tandem repeats (STRs) for investigative leads, and genotyping can now be streamlined using massively parallel sequencing (MPS). Dust is an attractive evidence source, as it accumulates on undisturbed surfaces, often is overlooked by perpetrators, and contains sufficient human DNA for analysis. To assess whether SNPs genotyped from indoor dust using MPS could be used to detect known household occupants, 13 households were recruited and provided buccal samples from each occupant and dust from five predefined indoor locations. Thermo Fisher Scientific Precision ID Identity and Ancestry Panels were utilized for SNP genotyping, and sequencing was completed using Illumina® chemistry. FastID, a software developed to permit mixture analysis and identity searching, was used to assess whether known occupants could be detected from associated household dust samples. A modified “subtraction” method was also used in FastID to estimate the percentage of alleles in each dust sample contributed by known and unknown occupants. On average, 72% of autosomal SNPs were recovered from dust samples. When using FastID, (a) 93% of known occupants were detected in at least one indoor dust sample and could not be excluded as contributors to the mixture, and (b) non-contributor alleles were detected in 54% of dust samples (29 ± 11 alleles per dust sample). Overall, this study highlights the potential of analyzing human DNA present in indoor dust to detect known household occupants, which could be valuable for investigative leads.  相似文献   
103.
Analogs of non-fentanyl novel synthetic opioids (NSO) with modifications that fall outside of established structure–activity relationships (SARs) for that class of drugs create the question whether or not it should be considered an analog, as defined by 21 U.S.C. §802(32)(A), which is important for its inclusion in the US system of drug scheduling. AH-7921 is a US Schedule I drug and an example of the 1-benzamidomethyl-1-cyclohexyldialkylamine class of NSO. The SARs regarding substitution of the central cyclohexyl ring have not been well characterized in the literature. Therefore, in order to expand the SAR surrounding AH-7921 analogs, trans-3,4-dichloro-N-[[1-(dimethylamino)-4-phenylcyclohexyl]methyl]-benzamide (AP01; 4-phenyl-AH-7921) has been synthesized, analytically characterized, and tested in vitro and in vivo pharmacologically. Using methods described in the original patents for this class of NSO, it was found that the single trans geometric isomer was obtained. The proton nuclear magnetic resonance, mass spectrum, infrared spectrum, and Raman spectrum are reported along with the melting point of the hydrochloride salt. In vitro binding to a battery of 43 central nervous system receptors showed it to be a high-affinity μ-opioid receptor (MOR) and κ-opioid receptor (KOR) ligand (60 nM and 34 nM, respectively). AP01 also had a 4 nM affinity for the serotonin transporter (SERT), which is a higher level of potency at this receptor than most other opioids. In rats, it exhibited antinociception in the acetic acid writhing test. Therefore, the 4-phenyl modification results in an active NSO, but carries with it potential toxicities beyond those expected for currently approved opioid drugs.  相似文献   
104.
With the emergence of new psychoactive substances (NPSs) over the years, the substances detected on stamps (also known as blotter papers) have also evolved from the traditional drug—lysergic acid diethylamide (LSD) to the multiple variants of lysergamides such as ALD-52 and 1P-LSD. The analysis of such blotter papers is usually done by solvent extraction followed by identification using gas chromatography–mass spectrometry (GC-MS). This study has shown that hydrolysis to form LSD was observed in GC-MS analysis when ALD-52 was extracted with methanol. The extraction of ALD-52 using other solvents such as acetonitrile, ethanol, isopropyl alcohol, ethyl acetate, and acetone, followed by GC-MS analysis, was investigated. It is shown that alcoholic solvents such as methanol and ethanol will result in the conversion of ALD-52 to LSD during GC-MS analysis, whereas the sterically hindered isopropyl alcohol will prevent this conversion. Investigation also shows that the hydrolysis of ALD-52 to LSD occurs at the GC injector port. It was also observed that the degree of hydrolysis was more pronounced at a lower concentration (0.1 mg/mL). The study was extended to a close analog—1P-LSD, and the results showed that 1P-LSD similarly hydrolyzes to LSD. However, 1P-LSD was observed to be more stable than ALD-52 due to steric hindrance because of the propanoyl group.  相似文献   
105.
The objective of this study is to assess the performance of an innovative AI-powered tool for sex determination using panoramic radiographs (PR) and to explore factors affecting the performance of the convolutional neural network (CNN). The study involved 207,946 panoramic dental X-rays and their corresponding reports from 15 clinical centers in São Paulo, Brazil. The PRs were acquired with four different devices, and 58% of the patients were female. Data preprocessing included anonymizing the exams, extracting pertinent information from the reports, such as sex, age, type of dentition, and number of missing teeth, and organizing the data into a PostgreSQL database. Two neural network architectures, a standard CNN and a ResNet, were utilized for sex classification, with both undergoing hyperparameter tuning and cross-validation to ensure optimal performance. The CNN model achieved 95.02% accuracy in sex estimation, with image resolution being a significant influencing factor. The ResNet model attained over 86% accuracy in subjects older than 6 years and over 96% in those over 16 years. The algorithm performed better on female images, and the area under the curve (AUC) exceeded 96% for most age groups, except the youngest. Accuracy values were also assessed for different dentition types (deciduous, mixed, and permanent) and missing teeth. This study demonstrates the effectiveness of an AI-driven tool for sex determination using PR and emphasizes the role of image resolution, age, and sex in determining the algorithm's performance.  相似文献   
106.
Metals can pose challenges while conducting forensic DNA analysis. The presence of metal ions in evidence-related DNA extracts can degrade DNA or inhibit PCR as applied to DNA quantification (real-time PCR or qPCR) and/or STR amplification, leading to low success in STR profiling. Different metal ions were spiked into 0.2 and 0.5 ng of human genomic DNA in an “inhibition study” and the impact was evaluated by qPCR using the Quantifiler™ Trio DNA Quantification Kit (Thermo Fisher Scientific) and an in-house SYBR Green assay. This study reports on a contradictory finding specific to tin (Sn) ions, which caused at least a 38,000-fold overestimation of DNA concentration when utilizing Quantifiler Trio. This was explained by the raw and multicomponent spectral plots, which indicated that Sn suppresses the Quantifiler Trio passive reference dye (Mustang Purple™, MP) at ion concentrations above 0.1 mM. This effect was not observed when DNA was quantified using SYBR Green with ROX™ as the passive reference, nor when DNA was extracted and purified prior to Quantifiler Trio. The results show that metal contaminants can interfere with qPCR-based DNA quantification in unexpected ways and may be assay dependent. The results also highlight the importance of qPCR as a quality check to determine steps for sample cleanup prior to STR amplification that may be similarly impacted by metal ions. Forensic workflows should recognize the risk of inaccurate DNA quantification of samples that are collected from substrates containing tin.  相似文献   
107.
The addition of information regarding obesity status to the forensic anthropological biological profile could significantly contribute to the identification of human skeletal remains since over 40% of the U.S. adult population is currently obese. This study examines the differences in talar shape and trabecular bone structure between obese and non-obese individuals. A sample of 20 obese and 20 non-obese divided evenly by sex was selected from the Texas State University Donated Skeletal Collection. Tali were imaged using x-ray computed tomography (voxel size: 28–38.7 μm). Image stacks were processed to produce binary images as well as trabecular thickness and spacing maps. Landmark-based geometric morphometric analyses were conducted to quantify shape variation. Shape coordinates were used to locate 100 geometrically homologous volumes of interest within each talus. Bone volume fraction, trabecular thickness, and trabecular spacing were extracted at each volume of interest. Within each sex, a one-way ANCOVA was used to determine if significant differences exist between obese and non-obese individuals in trabecular bone after controlling for age. The size of the talus as well as subtle aspects of shape were found to distinguish the sexes. The results further indicate that bone volume fraction significantly differs between obese and non-obese males. In females, bone volume fraction is correlated with age but does not differ between obese and non-obese. The study demonstrates that bone microstructure is a promising approach to estimating body mass or body mass index category but age effects diminish the potential for the talus to be used alone.  相似文献   
108.
Potent synthetic opioids including fentanyl and its analogs are frequently encountered in the field and require detection and identification by first responders to maintain the safety of drug abusers, first responders, health-care providers, and the public at large. Due to the low concentration at which these substances may be encountered and the complicating matrices within which they may be dispersed, the use of portable gas chromatography–mass spectrometry (GC–MS) for their identification in the field offers great potential value. This research established that portable GC–MS is a useful method for the detection and identification of a large number of synthetic opioids, especially fentanyl and its analogs. In this study, 250 synthetic opioids and related substances including 210 fentanyl analogs were analyzed using portable GC–MS. It was concluded that 225 of the 250 (90.0%) opioids analyzed were successfully detected onboard at the time of analysis and identified as either the substance (55.2%) or an analog (34.8%). These outcomes have equivalent benefit for the field analysis of illicit drugs due to both initiating the same subsequent actions by first responders.  相似文献   
109.
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   
110.
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   
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