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891.
The implementation of peacebuilding activities, including the demobilization of non-state illegal actors, does not necessarily bring about a reduction in violence. While there are several theories that address the causes of persistent violence, there are few that adequately explain why rates of violence can rapidly increase in a post-demobilization context. Using the method of process tracing, this article explores the case of Córdoba Department, Colombia, where rates of violence have increased after the demobilization of paramilitary groups (Autodefensas Unidas de Colombia [AUC]) in 2005. We argue that the AUC created and maintained a monopolistic illegal protection system during its years of operation, and this type of local order was able to contain violence. After demobilization, the protection system was disrupted and as a consequence, new competition between post-demobilization criminal organizations for existing illegal rents developed, petty crime became pervasive, and revenge killings spiked, thus contributing to increased rates of violence in the post-demobilization period. Our theory about the breakdown of protection finds support in other AUC-dominated regions of Colombia. 相似文献
892.
Daniel Gaudio B.Sc. Ph.D. Lara Olivieri B.A. Danilo De Angelis M.D. Ph.D. Pasquale Poppa B.Sc. Ph.D. Andrea Galassi M.D. Cristina Cattaneo B.Sc. M.A. M.D. Ph.D. 《Journal of forensic sciences》2016,61(1):5-11
Craniofacial superimposition is a technique potentially useful for the identification of unidentified human remains if a photo of the missing person is available. We have tested the reliability of the 2D‐3D computer‐aided nonautomatic superimposition techniques. Three‐dimension laser scans of five skulls and ten photographs were overlaid with an imaging software. The resulting superimpositions were evaluated using three methods: craniofacial landmarks, morphological features, and a combination of the two. A 3D model of each skull without its mandible was tested for superimposition; we also evaluated whether separating skulls by sex would increase correct identifications. Results show that the landmark method employing the entire skull is the more reliable one (5/5 correct identifications, 40% false positives [FP]), regardless of sex. However, the persistence of a high percentage of FP in all the methods evaluated indicates that these methods are unreliable for positive identification although the landmark‐only method could be useful for exclusion. 相似文献
893.
Kaitlyn B. Palmquist PhD Michael T. Truver PhD Elisa N. Shoff MS Alex J. Krotulski PhD Madeleine J. Swortwood PhD 《Journal of forensic sciences》2023,68(5):1643-1661
Fentanyl, fentanyl analogs, and other novel synthetic opioids (NSO), including nitazene analogs, prevail in forensic toxicology casework. Analytical methods for identifying these drugs in biological specimens need to be robust, sensitive, and specific. Isomers, new analogs, and slight differences in structural modifications necessitate the use of high-resolution mass spectrometry (HRMS), especially as a non-targeted screening method designed to detect newly emerging drugs. Traditional forensic toxicology workflows, such as immunoassay and gas chromatography mass spectrometry (GC–MS), are generally not sensitive enough for detection of NSOs due to observed low (sub-μg/L) concentrations. For this review, the authors tabulated, reviewed, and summarized analytical methods from 2010–2022 for screening and quantification of fentanyl analogs and other NSOs in biological specimens using a variety of different instruments and sample preparation approaches. Limits of detection or quantification for 105 methods were included and compared to published standards and guidelines for suggested scope and sensitivity in forensic toxicology casework. Methods were summarized by instrument for screening and quantitative methods for fentanyl analogs and for nitazenes and other NSO. Toxicological testing for fentanyl analogs and NSOs is increasingly and most commonly being conducted using a variety of liquid chromatography mass spectrometry (LC–MS)-based techniques. Most of the recent analytical methods reviewed exhibited limits of detection well below 1 μg/L to detect low concentrations of increasingly potent drugs. In addition, it was observed that most newly developed methods are now using smaller sample volumes which is achievable due to the sensitivity increase gained by new technology and new instrumentation. 相似文献
894.
Alastair Ruffell PhD Benjamin Rocke BSc Neil Powell PhD 《Journal of forensic sciences》2023,68(4):1379-1385
In the absence of surface indications of burial sites, law enforcement or humanitarian organizations are faced with the difficult task of focusing large-scale ground searches to a manageable excavation area. A geoforensic-based survey may exclude parts of the landscape for reasons such as diggability or viewshed analysis but leave areas still too large for invasive exploration. This work examines how drone-based remote sensing, geophysics, and search dogs may be combined to narrow such searches. Here, we ask the reader to consider two examples where forensic geomorphology and land use provided a range of possible burial locations. Following this is a multi-proxy approach to similar dilemma, with a search-to-scene case study using remote sensing (drone photography), geophysics, ground probes, and search dogs. This approach is not presented as a definitive guide, but serves as an example of the conjunctive use of well-studied methods to approach a common problem in geoforensics. 相似文献
895.
Paul Ippoliti MS Jeffrey Werlich BS Cami Fuglsby MS Chris Yarnes PhD Christopher P. Saunders PhD Josh Dettman PhD 《Journal of forensic sciences》2023,68(2):407-415
Forensic science practitioners are often called upon to attribute crimes using trace evidence, such as explosive remnants, with the ultimate goal of associating a crime with a suspect or suspects in order to prevent further attacks. The explosive charge is an attractive component for attribution in crimes involving explosives as there are limited pathways for acquisition. However, there is currently no capability to link an explosive charge to its source via post-blast trace residues using isotope ratios or trace elements. Here, we sought to determine if pre-blast attribution signatures are preserved after detonation and can be subsequently recovered and detected. A field study was conducted to recover samples of post-blast explosives from controlled detonations of ammonium nitrate-aluminum (AN-Al), which were then analyzed via isotope ratio mass spectrometry (IRMS) and inductively coupled plasma-mass spectrometry (ICP-MS) for quantitation and profiling of isotopes ratio and trace element signatures, respectively. Oxygen and nitrogen isotope ratios from AN-Al yielded some of the most promising results with considerable overlap within one standard deviation of the reference between the spreads of pre- and post-blast data. Trace element results from AN-Al support the findings in the isotope ratio data, with 26 elements detected in both pre- and post-blast samples, and several elements including B, Cd, Cr, Ni, Sn, V, and Zn showing considerable overlap. These preliminary results provide a proof-of-concept for the development of forensic examinations that can attribute signatures from post-blast debris to signatures in pre-blast explosive materials for use in future investigations. 相似文献
896.
A new, fast, and ultra-sensitive headspace sampling method using the Capillary Microextraction of Volatiles (CMV) device is demonstrated for the analysis of ignitable liquid residues (ILRs) in fire debris. This headspace sampling method involves the use of a heated can (60°C) to aid in the recovery of volatile organic compounds (VOCs) from medium and heavy petroleum distillates. Our group has previously reported the utility of CMV to extract gasoline at ambient temperature in less than 5 min in the field. This work evaluates the recovery and analysis of low mass loadings (tens of ng) of VOCs from charcoal lighter fluid, kerosene, and diesel fuel. Nonane, decane, undecane, tridecane, tetradecane, and pentadecane were selected for evaluation of recovery to represent these ILR classes. The face-down heated can headspace sampling technique was compared to the previously reported, non-heated, paper cup headspace sampling technique. Mass recovery improvements of 50%–200% for five of the six target compounds in diesel fuel were achieved compared to the non-heated sampling method. The average relative standard deviation (reported as % RSD) between the replicate trials decreased from an average of 28% to 6% when using the heated can method. Ignitable liquids were spiked onto burned debris in a live burn exercise and sampled using the heated can and paper cup headspace sampling techniques. The heated sampling technique reported here, for the first time, demonstrates an effective extraction method that when coupled to a portable GC–MS instrument allows for a sampling and analysis protocol in the field in less than 30 min. 相似文献
897.
Angelina Sferra 《Family Court Review》2023,61(1):175-188
New York precedent has mischaracterized Islamic marriage contracts, or nikah agreements, as premarital agreements. Nikah agreements are not premarital agreements; they are contracts. This mischaracterization has subjected nikah agreements to the acknowledgement requirement codified in N.Y. DRL § 236(B)(3) which has incorrectly been used to strike down valid contracts which Islamic litigants rely on. To prevent the effects of this mischaracterization, this Note suggests to New York appellate courts that a recharacterization of these agreements as contracts would prevent further confusion amongst the lower courts and allow for clearer, more uniform decisions. 相似文献
898.
John L. Krstenansky PhD MBA John Bacsa PhD Alexander Zambon PhD 《Journal of forensic sciences》2023,68(3):978-989
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
899.
Jyoti Dalal PhD Sapna Sharma PhD Tapeshwar Bhardwaj MSc S. K. Dhattarwal PhD 《Journal of forensic sciences》2023,68(2):549-557
Investigating drowning-related deaths remains a significant problem for forensic personnel all over the world. The previously published decomposition scoring method like the total aquatic decomposition (TAD) score promises to estimate the correct post-mortem submersion interval (PMSI) in aquatic habitats through the assessment and calculation of the decomposition rate and accumulated degree days (ADD). The current study comprised of 53 drowned death cases belonging to various districts of Haryana from May 2016 to August 2017. The regression and Pearson's correlation indicated a significant correlation between the TAD scores and the actual ADD (calculated through water temperatures) (r2 = 0.917) and between the actual and the estimated ADDs (calculated through TAD scores used by Heaton et al. [21]) (r = 0.9585). The results indicated that the estimated ADD tends to over predict the PMSI compared to the actual ADD. It is further confirmed by paired t-test, which showed the mean of actual ADD (mean = 349) to be significantly lower than the mean of estimated ADD (mean = 663). Moreover, these methods will help forensic investigators and researchers formulate region-specific regression equations for PMSI estimation. 相似文献
900.
In recent years, the European continent has witnessed a substantial number of “transboundary crises” – crises that cross geographical borders and affect multiple policy domains. Nation states find it hard to deal with such crises by themselves. International cooperation, thus, becomes increasingly important, but it is not clear what shape or form that cooperation should take. This article explores the growing role of the European Union (EU) in managing transboundary crises. More specifically, it reflects on the different ways in which the expanding contours of the EU's emerging crisis capacity can be organized. Using three “performative dimensions” – sense‐making, coordination, and legitimacy – the article discusses the possible advantages and disadvantages of a decentralized, network model and compares it with a more centralized, lead‐agency model. It concludes that the current network model is a logical outcome of the punctuated and fragmentary process through which EU crisis management capacities have been created. It also notes that the shortcomings of this model may necessitate elements of a lead‐agency model. Such “agencification” of networks for transboundary crisis management may well lead to a hybrid model that is uniquely suited for the peculiar organizational and political creature that the EU is. 相似文献