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This paper assesses the various peace and security mechanisms that African regional organisations are establishing and other measures that they are taking to enhance their preparedness. In the mid-1990s, the United Nations (UN) Security Council responded to the widely perceived failures of several UN peacekeeping operations by encouraging regional arrangements and agencies to assume a greater role in the promotion of peace and security. As of December 2001, four African organisations had authorised 17 peacekeeping missions. Most of them have been beset by serious and sustained operational and political shortcomings. Recognising their limitations and the vacuum created by Security Council inaction, these and other organisations have undertaken various initiatives to improve on past performance and to prepare for future engagements. A review of their decision-making processes, staffing, mission planning and support, peacekeeping training and financial resources suggests that, while they have made some progress, most organisations are still far from being able to take on the responsibilities that the international community would like them to assume. 相似文献
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Camposortega Cruz S 《Estudios demográficos y urbanos》1989,4(2):229-64, 429
The author analyzes mortality trends in Mexico in the twentieth century, particularly since 1940. Trends are examined according to age, sex, and cause of death. The decline in mortality is then considered in the context of the country's history and other mortality transitions. Regional variations and excess mortality are also described. (SUMMARY IN ENG) 相似文献
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Tiffany R. Layne M.S. Raquel A. Green B.S. Carolyn A. Lewis B.S. Francy Nogales B.S. Tracey C. Dawson Cruz Ph.D. Zendra E. Zehner Ph.D. Sarah J. Seashols‐Williams Ph.D. 《Journal of forensic sciences》2019,64(6):1831-1837
Evaluation of microRNA (miRNA) expression as a potential method for forensic body fluid identification has been the subject of investigation over the past several years. Because of their size and encapsulation within proteins and lipids, miRNAs are inherently less susceptible to degradation than other RNAs. In this work, blood, urine, semen, and saliva were exposed to environmental and chemical conditions mimicking sample compromise at the crime scene. For many treated samples, including 100% of blood samples, miRNAs remained detectable, comparable to the untreated control. Sample degradation varied by body fluid and treatment, with blood remarkably resistant, while semen and saliva are more susceptible to environmental insult. Body fluid identification using relative miRNA expression of blood and semen of the exposed samples was 100% and 94%, respectively. Given the overall robust results herein, the case is strengthened for the use of miRNAs as a molecular method for body fluid identification. 相似文献
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José Miguel Cruz 《拉美政治与社会》2011,53(4):1-33
Why does Nicaragua have less violent crime than Guatemala, El Salvador, and Honduras? All these countries underwent political transitions in the 1990s. Many explanations point to the legacies of war, socioeconomic underdevelopment, and neoliberal structural reforms. However, these arguments do not fully explain why, despite economic reforms conducted throughout the region, war‐less Honduras and wealthier Guatemala and El Salvador have much more crime than Nicaragua. This article argues that public security reforms carried out during the political transitions shaped the ability of the new regimes to control the violence produced by their own institutions and collaborators. In the analysis of the crisis of public security, it is important to bring the state back. The survival of violent entrepreneurs in the new security apparatus and their relationship with new governing elites foster the conditions for the escalation of violence in northern Central America. 相似文献
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Lendoiro E Quintela O de Castro A Cruz A López-Rivadulla M Concheiro M 《Forensic science international》2012,217(1-3):207-215
A liquid chromatography-tandem mass spectrometry (LC-MSMS) target screening in 50mg hair was developed and fully validated for 35 analytes (Δ9-tetrahidrocannabinol (THC), morphine, 6-acetylmorphine, codeine, methadone, fentanyl, amphetamine, methamphetamine, 3,4-methylenedioxyamphetamine, 3,4-methylenedioxymethamphetamine, benzoylecgonine, cocaine, lysergic acid diethylamide, ketamine, scopolamine, alprazolam, bromazepam, clonazepam, diazepam, flunitrazepam, 7-aminoflunitrazepam, lorazepam, lormetazepam, nordiazepam, oxazepam, tetrazepam, triazolam, zolpidem, zopiclone, amitriptyline, citalopram, clomipramine, fluoxetine, paroxetine and venlafaxine). Hair decontamination was performed with dichloromethane, and incubation in 2 mL of acetonitrile at 50°C overnight. Extraction procedure was performed in 2 steps, first liquid-liquid extraction, hexane:ethyl acetate (55:45, v:v) at pH 9, followed by solid-phase extraction (Strata-X cartridges). Chromatographic separation was performed in AtlantisT3 (2.1 mm × 100 mm, 3 μm) column, acetonitrile and ammonium formate pH 3 as mobile phase, and 32 min total run time. One transition per analyte was monitored in MRM mode. To confirm a positive result, a second injection monitoring 2 transitions was performed. The method was specific (no endogenous interferences, n=9); LOD was 0.2-50 pg/mg and LOQ 0.5-100 pg/mg; linearity ranged from 0.5-100 to 2000-20,000 pg/mg; imprecision <15%; analytical recovery 85-115%; extraction efficiency 4.1-85.6%; and process efficiency 2.5-207.7%; 27 analytes showed ion suppression (up to -86.2%), 4 ion enhancement (up to 647.1%), and 4 no matrix effect; compounds showed good stability 24-48 h in autosampler. The method was applied to 17 forensic cases. In conclusion, a sensitive and specific target screening of 35 analytes in 50mg hair, including drugs of abuse (THC, cocaine, opiates, amphetamines) and medicines (benzodiazepines, antidepressants) was developed and validated, achieving lower cut-offs than Society of Hair Testing recommendations. 相似文献
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