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111.
112.
Abstract: Organic impurity profiling of seized 3,4‐methylenedioxymethamphetamine (MDMA) tablets aims to link tablets to common production sources. Conventionally, organic impurities are extracted from tablets using a liquid–liquid extraction (LLE) procedure prior to analysis by gas chromatography–mass spectrometry (GC‐MS). In this research, the development of an alternative microwave‐assisted extraction/headspace solid‐phase microextraction (MAE/HS‐SPME) procedure is described. The optimal procedure used phosphate buffer (1 M, pH 8), with an HS‐SPME extraction temperature of 70°C for 40 min, using a divinylbenzene/Carboxen?/polydimethylsiloxane (DVB/CAR/PDMS) fiber. Impurities were extracted from seized MDMA exhibits using the MAE/HS‐SPME procedure, as well as HS‐SPME alone, and a conventional LLE procedure. The HS‐SPME procedure was deemed to be the most practical because of the affordability and need for less analyst involvement. Although the LLE was limited in the number of impurities extracted, the procedure is still useful for the extraction of less volatile impurities that are not extracted by HS‐SPME. 相似文献
113.
A combined analysis of microcrystalline tests followed by LC-MS or GC-MS analysis is described. Microcrystalline tests are shown to be non-destructive as addition products formed were easily dissociated after the application of an appropriate solvent. Subsequent analysis of the sample was done to quantify the recovery of the drug. Examples were performed using the date rape drug γ-hydroxybutyrate (GHB) and the synthetic opioid methadone. 相似文献
114.
The Condorcet Jury Theorem (CJT), which provides a justification for democracy, is based on voters who are imperfectly informed insofar as they know the correct policy with a probability of less than one but greater than one-half. We reassess the consequences of the CJT for democracy when extension of the franchise adds equal numbers of non-distinguishable informed and uninformed voters to the collective decision making group. Uninformed voters vote correctly with probability one-half. We show that adding equal numbers of informed and uninformed voters maintains the CJT conclusion that enlarging the group of decision makers increases the likelihood of a correct collective decision. 相似文献
115.
Ruth Roded 《British Journal of Middle Eastern Studies》2006,33(1):51-66
The Egyptian writer and Islamic scholar Dr. cA'isha cAbd al-Rahman (b. 1913), who originated from the countryside, was a pioneering woman in many respects, although she did not consider herself to be a feminist. She was one of the first Egyptians to write about the agrarian problems of the country and the plight of the peasants; and of the pioneering generation of female Arab literati. She was also the first Muslim woman to undertake Quranic exegesis. Writing under her pen name, Bint al-Shati', she was also one of the first women to deal with the life of the Prophet Muhammad through vignettes of the women in his life. Like many other modern Muslim biographers of the Prophet, she rendered classical Islamic materials in a new style. Although her book on the Wives of the Prophet often portrays women in a negative light, content analysis indicates that the work also reflects feminist themes. 相似文献
116.
Identification of an ignitable liquid in fire debris evidence can be complicated due to evaporation of the liquid, matrix interferences, and thermal degradation of both the liquid and the matrix. In this research, liquids extracted from simulated fire debris were compared to the original liquid using multivariate statistical procedures. Neat and evaporated gasoline and kerosene standards were spiked onto nylon carpet, which was subsequently burned. The ignitable liquid residues were extracted using a passive headspace procedure and analyzed by gas chromatography-mass spectrometry. Pearson product moment correlation coefficients, hierarchical cluster analysis, and principal components analysis were used to compare the liquids extracted from the carpet to the corresponding neat liquid. For each procedure, association of the extracts according to liquid type was possible, albeit not necessarily to the specific evaporation level. Of the three procedures investigated, principal components analysis offered the most promise since contributions from matrix interferences were essentially eliminated. 相似文献
117.
118.
Tharp AM Winecker RE Winston DC 《The American journal of forensic medicine and pathology》2004,25(2):178-181
The transdermal fentanyl system delivers a specific dose at a constant rate. Even after the prescribed application time has elapsed, enough fentanyl remains within a patch to provide a potentially lethal dose. Death due to the intravenous injection of fentanyl extracted from transdermal patches has not been previously reported. We present 4 cases in which the source of fentanyl was transdermal patches and was injected. In all of these cases, the victim was a white male who died at home. Case 1 was a 35-year-old with no known history of drug use, who was found by his wife on the floor of his workshop. Police recovered a fentanyl patch, needle, and syringe at the scene. Case 2 was a 38-year-old with a known history of drug use whose family claimed that he was in a treatment program that used fentanyl patches for unknown reasons. His brother found him dead in bed, and law enforcement officers found a hypodermic needle beside the body; a ligature around his left hand, and apparent needle marks between his first and second digits were also noted. Case 3 was a 42-year-old with a recent attempted suicide via overdose who was found dead at his home. An empty box of fentanyl patches, Valium, Ritalin, and 2 syringes were found at the scene. Case 4 was a 39-year-old found by his mother, who admitted to removing a needle with attached syringe from the decedent's arm. Medications at the scene included hydrocodone, alprazolam, zolpidem, and fentanyl patches. All reported deaths were attributed to fentanyl intoxication, with blood concentrations ranging from 5 to 27 microg/L. 相似文献
119.
120.
Treatment efficacy is described for a sample of sexual offenders who had undertaken treatment in United Kingdom prisons (N = 647) and for a retrospectively selected comparison group (N = 1,910). The outcomes under observation in this study were sexual, sexual and/or violent, and general reconviction. Treatment impact was also examined in relation to offenders' risk of reconviction. The treatment group had slightly lower 2-year sexual reconviction rates than the comparison group, but these differences were not statistically significant. Significant differences were found between the treatment and comparison group for sexual and/or violent reconviction. Further analysis suggested that treatment produced a reduction in the probability of sexual and/or violent reconviction (p <.05) when other relevant variables were controlled for. General reconviction rates were consistently lower in the treatment group, but these differences were not significant. 相似文献