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191.
Andrew M. Sacha BS Isaac C. Willis BS Victoria L. McGuffin PhD Ruth Waddell Smith PhD 《Journal of forensic sciences》2023,68(5):1527-1541
Definitive identification of fentanyl analogs based on mass spectral comparison is challenging given the high degree of structural and, hence, spectral similarity. To address this, a statistical method was previously developed in which two electron-ionization (EI) mass spectra are compared using the unequal variance t-test. Normalized intensities of corresponding ions are compared, testing the null hypothesis (H0) that the difference in intensity is equal to zero. If H0 is accepted at all m/z values, the two spectra are statistically equivalent at the specified confidence level. If H0 is not accepted at any m/z value, then there is a significant difference in intensity at that m/z value between the two spectra. In this work, the statistical comparison method is applied to distinguish EI spectra of valeryl fentanyl, isovaleryl fentanyl, and pivaloyl fentanyl. Spectra of the three analogs were collected over a 9-month period and at different concentrations. At the 99.9% confidence level, the spectra of corresponding isomers were statistically associated. Spectra of different isomers were statistically distinct, and ions responsible for discrimination were identified in each comparison. To account for inherent instrument variations, discriminating ions for each pairwise comparison were ranked based on the magnitude of the calculated t-statistic (tcalc) value. For a given comparison, ions with higher tcalc values are those with the greatest difference in intensity between the two spectra and, therefore, are considered more reliable for discrimination. Using these methods, objective discrimination among the spectra was achieved and ions considered most reliable for discrimination of these isomers were identified. 相似文献
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Prior research suggested that when community members are notified that a sex offender is residing in their neighborhood they are likely to engage in precautionary behavior to prevent potential victimization. Since states employ different processes in notifying community members of the presence of a sex offender, it is important to examine the advantages and disadvantages of the various notification processes. The current exploratory study compared the proactive sex offender notification process in Hamilton County, Ohio, with the passive notification process in Jefferson County, Kentucky. Not surprisingly, study findings indicated that the proactive sex offender notification process used in Ohio resulted in better community dissemination of information. 相似文献
195.
This is a second and important judgment in the H Trust litigation,which was first before the Royal Court in April 2006. At thathearing, the Royal Court directed the Jersey resident trusteeof the H Trust not to take any part in English divorce proceedingsbetween a husband and wife, both of whom were beneficiariesunder the H Trust, but to provide full information to the partiesfor use in the English High Court. The husband was the settlorof the H Trust. The Royal Court also encouraged the trusteeto assist in giving effect to any reasonable arrangement 相似文献
196.
Sergey Afontsev Gijs Kessler Andrei Markevich Victoria Tyazhelnikova Timur Valetov 《The History of the Family》2008,13(2):178
Starting from census data on co-residence and household composition, the authors analyse principles of family organisation and family formation in twentieth-century urban Russia and the Soviet Union. The article uses an adapted version of the classification of households developed by Peter Laslett and Eugene Hammel to study variation in household structure for successive population censuses. Changes in this variation between cross-sections are explained with the help of additional quantitative and qualitative data and are linked to the fundamental demographic, social and economic shifts which took place in Russian society in the course of the twentieth century. The article finds a family system characterised by a tendency towards nuclear family formation, but incorporating a fairly stable element of household extension. Co-residence of three generations was both an answer to a perennial housing problem and offered important advantages in the sphere of childcare and care for the elderly. Variation and fluctuation in household structure are found to be most pronounced during the turbulent first half of the century. After a period of stability during the post-war decades of Soviet rule, post-Soviet transformations provoke new changes. 相似文献
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This article suggests measures that should be taken to ensure, as much as possible, the safety of victims of domestic violence. Because victims and perpetrators of domestic violence will inevitably be attendees at parent education programs, such programs must be sensitive to the safety concerns of these victims. Only when victims of domestic violence are safe will their children be safe and able to benefit from what their parents learn at these education programs. This article concludes that, by weaving common-sense logistical, administrative, and curricular recommendations into the fabric of every parent education program, the safety of victims and children will be prioritized as it must be, while all attendees still receive the maximum benefit from these valuable programs. 相似文献
200.
Soderquist TJ Chesniak OM Witt MR Paramo A Keeling VA Keleher JJ 《Forensic science international》2012,218(1-3):101-105
Hair testing for drugs of abuse is performed in Lombardy by eleven analytical laboratories accredited for forensic purposes, the most frequent purposes being driving license regranting and workplace drug testing. Individuals undergoing hair testing for these purposes can choose the laboratory in which the analyses have to be carried out. The aim of our study was to perform an interlaboratory exercise in order to verify the level of standardization of hair testing for drugs of abuse in these accredited laboratories; nine out of the eleven laboratories participated in this exercise. Sixteen hair strands coming from different subjects were longitudinally divided in 3-4 aliquots and distributed to participating laboratories, which were requested to apply their routine methods. All the participants analyzed opiates (morphine and 6-acetylmorphine) and cocainics (cocaine and benzoylecgonine) while only six analyzed methadone and amphetamines (amphetamine, methamphetamine, MDMA, MDA and MDEA) and five Δ(9)-tetrahydrocannabinol (THC). The majority of the participants (seven labs) performed acidic hydrolysis to extract the drugs from the hair and analysis by GC-MS, while two labs used LC-MS/MS. Eight laboratories performed initial screening tests by Enzyme Multiplied Immunoassay Technique (EMIT), Enzyme-linked Immunosorbent Assay (ELISA) or Cloned Enzyme Donor Immunoassay (CEDIA). Results demonstrated a good qualitative performance for all the participants, since no false positive results were reported by any of them. Quantitative data were quite scattered, but less in samples with low concentrations of analytes than in those with higher concentrations. Results from this first regional interlaboratory exercise show that, on the one hand, individuals undergoing hair testing would have obtained the same qualitative results in any of the nine laboratories. On the other hand, the scatter in quantitative results could cause some inequalities if any interpretation of the data is required. 相似文献