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41.
Synthetic opioids such as fentanyl account for over 71,000 of the approximately 107,000 overdose deaths reported in the United States in 2021. Fentanyl remains the fourth most identified drug by state and local forensic laboratories, and the second most identified drug by federal laboratories. The unambiguous identification of fentanyl-related substances (FRS) is challenging due to the absence or low abundance of a molecular ion in a typical gas chromatography-mass spectrometry (GC-MS) analysis and due to a low number of fragment ions that are similar among the many potential isomers of FRS. This study describes the utility of a previously reported gas chromatography-infrared (GC-IR) library for the identification of FRS within a blind, interlaboratory study (ILS) involving seven forensic laboratories. Twenty FRS reference materials, including those with isomer pairs in the library, were selected based on either their presence in the NIST library and/or some similarity of the mass spectra information produced. The ILS participants were requested to use the Florida International University (FIU) GC-MS and GC-IR libraries supplied by FIU to search for matches to their unknown spectra generated from in-house GC-MS and GC-IR analysis. The laboratories reported improvement in the positive identification of unknown FRS from ~75% using GC-MS alone to 100% correct identification using GC-IR analysis. One laboratory participant used solid phase IR analysis, which produced spectra incompatible with the vapor phase GC-IR library to generate a good comparison spectrum. However, this improved when searched against a solid phase IR library.  相似文献   
42.
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   
43.
Statebuilding after conflict often entails liberal peacebuilding measures. The end of the UN mission in post‐conflict Timor‐Leste in December 2012 provides a unique opportunity to investigate statebuilding in practice. The liberal peacebuilding agenda has met with stiff academic resistance—mainly from the critical theorist camp—and is questioned as an appropriate measure of …statebuilding success. We deploy instead the good governance (GG) agenda as a hybrid local‐liberal guide. Drawing on field work, interviews, and secondary documents, we investigate what we see as four key, intertwined and overlapping aspects of GG: state capacity including the establishment of a state bureaucracy, participation and the engagement of civil society, institution building and rule of law, and corruption control and transparency. We note GG provides a useful policy heuristic, while abstract “one‐size‐fits‐all” liberal peacebuilding models, which avoid the complexities of machinery of government issues, the time taken to develop institutions, and historical and contextual environments of countries, are likely to face severe problems. New states may be dependent on external forces to maintain monopoly of violence. The reversibility and uncertainty of statebuilding and the decades‐long commitment needed by international agencies are noted. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
44.
ABSTRACT

The author of this article is one of the attorneys appointed to represent Zacarias Moussaoui in the United States. Mr. Moussaoui is the only person facing criminal charges for alleged involvement in the September 11 plot. The author describes the system of government in the United States with a specific emphasis on several terrorism cases pending in the United States. He seeks to assure the readers that the rule of law is paramount in the United States. Recent decisions of the Supreme Court—in the Hamdi and Guantanamo cases—that confirm the constitutional rights of even the most dedicated enemies of the United States, which decisions post-date this submission, only affirm the writer's theme.  相似文献   
45.
We report the results of a study examining the effects of vertical strategic alignment (that is, the degree to which strategic stances are consistent across different organizational levels) on public service performance. Longitudinal multivariate analysis is undertaken on a panel of public organizations over four years. We find that alignment on a prospecting strategy leads to better performance, but that no such effect is observed for a defending strategy. We also find that high levels of prospecting alignment produce stronger positive performance effects in centralized organizations and when environmental uncertainty is high. The implications of these findings for research and practice are considered in the conclusion.  相似文献   
46.
The purpose of this research is to investigate a method for the forensic elemental analysis of cotton fibers for the purpose of increasing the discrimination between otherwise similar cotton evidence using microwave digestion inductively coupled plasma mass spectrometry (ICP-MS) and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). A quadrupole ICP-MS and UV laser ablation (266 nm) instruments were used for the analysis. A cotton standard reference material (IAEA V-9) was used to validate the developed methods producing good accuracy with typically <10% bias and good precision (typically <5% RSD) for the element list: 25Mg, 27Al, 55Mn, 57Fe, 88Sr and 137Ba. It was found that the LA-ICP-MS method resulted in improved precision over the solution ICP-MS method. Twenty-four raw cotton samples and five white cotton T-shirts were analyzed with the developed methods. It was also found that all the raw cotton samples from different sources were distinguishable from each other, as were all the cotton T-shirts resulting in zero type I errors and zero type II errors for the pairwise comparisons. The laser ablation method was slightly faster than the solution-based analysis, requiring 3 h for the laser analysis of 10 samples vs. 3.5 h for the solution analysis, including sample preparation time. One additional advantage of the LA-ICP-MS method was the extremely low sample consumption (1.75 μg were consumed vs. 250 mg for the solution-based method) and the fact that the LA samples are amenable for reanalysis.  相似文献   
47.
In the autumn of 1962, two weeks before U-2 aerial photographs confirmed Soviet deployments of nuclear missiles in Cuba, the US intelligence community attempted to image the island with the spy satellite Corona. Insufficient image resolution and extensive cloud cover, however, prevented this photography from providing solid evidence confirming or denying the presence of offensive missiles. This event – previously unaddressed either by Missile Crisis or Corona scholars – illustrates both the promise and the limits of early satellite imagery intelligence. It further provides insight into the early imagery tasking and coordination process and demonstrates needs that drove further development of national satellite reconnaissance in the years that followed.  相似文献   
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Gamma-Hydroxybutyric acid (GHB) is a CNS depressant that has been abused recreationally for its purported euphoric and relaxation effects and for the purposes of drug facilitated sexual assault due to its sedative and amnesic effects at higher doses. The dramatic increase in the abuse of GHB and association in criminal investigations over the past decade has created the need for forensic laboratories to develop analytical methods to detect GHB in a variety of matrices. The method developed in this work used solid-phase microextraction (SPME) to extract GHB from aqueous samples followed by on-fiber derivatization and analysis by gas chromatography/mass spectrometry (GC/MS). This method detected GHB in aqueous matrices with good sensitivity, high precision, excellent linearity from 0.01 mg/mL to 0.25 mg/mL, and without the need for sample manipulation that could cause interconversion between GHB and its lactone, GBL. The method was successfully applied for detection of GHB in spiked water and beverage samples.  相似文献   
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