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71.
Allele frequencies for 16 previously described autosomal SNPs were tested in 1020 unrelated individuals originating from three different continents (Africa, Asia and Europe). The populations analyzed included Africans from Benin Gulf (180), Asians from Mongolia (160) and Europeans from Italy (680).  相似文献   
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A population study on two new short tandem repeat (STR) loci D6S477 and D19S433 was performed on 214 unrelated Italian Caucasians. The DNA was amplified by PCR and separation and detection of the amplified STR fragments were carried out by use of a PE/ABD PRISM 377 DNA sequencer 377 automated system (Applied Biosystems Division/Perkin Elmer). Both loci meet Hardy-Weinberg expectations. There is no evidence for departures from expectations between the two loci. The combined probability of discrimination and probability of exclusion for the two STR loci are 0.997161 and 0.883183, respectively. The results demonstrate that these loci can be useful for human identification in forensic cases in Italy.  相似文献   
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The quali-quantitative determination of two barbiturates, thiopental and its metabolite pentobarbital, in head and pubic hair samples of a woman who had been sexually assaulted during hospitalisation, is reported. Hair was analysed by means of solid-phase microextraction (SPME) and gas chromatography-multiple mass spectrometry (GC-MS-MS), in chemical ionisation conditions. Thiopental and pentobarbital were found in three proximal head hair segments (sample 1A: 0.30 and 0.40 ng/mg; sample 1B: 0.20 and 0.20 ng/mg; sample 3: 0.15 and 0.20 ng/mg) and pubic hair sample. Two distal head hair segments were negative for both barbiturates. Despite the lack of collection and toxicological analysis of blood or urine samples within the hospital setting, analytical findings from hair revealed the use of the anaesthetic agent thiopental to sedate the victim quickly and deeply and commit sexual assault.  相似文献   
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The opioid epidemic has affected the United States (US) for decades with fentanyl and its analogs accounting for a recent surge in morbidity and mortality. Currently, there is a relative lack of information characterizing fentanyl-related fatalities specifically in the Southern US. A retrospective study was conducted to examine all postmortem fentanyl-related drug toxicities in Travis County, Texas, encompassing Austin (one of the fastest-growing cities in the US), from 2020 to 2022. Fentanyl contributed to 2.6% and 12.2% of deaths submitted for toxicology between 2020 and 2022, respectively, representing a 375% increase in fentanyl-related deaths over this 3-year period (n = 517). Fentanyl-related fatalities primarily occurred in males in their mid-30s. Fentanyl and norfentanyl concentrations ranged from 0.58 to 320 ng/mL and 0.53 to 140 ng/mL with mean (median) concentrations of 17.2 ± 25.0 (11.0) and 5.6 ± 10.9 (2.9) ng/mL, respectively. Polydrug use was present in 88% of cases, with methamphetamine (or other amphetamines) (25%), benzodiazepines (21%), and cocaine (17%) representing the most frequently identified concurrent substances. Co-positivity rates of various drugs and drug classes widely varied over time. Scene investigations reported illicit powder(s) (n = 141) and/or illicit pill(s) (n = 154) in 48% (n = 247) of fentanyl-related deaths. Illicit oxycodone (44%, n = 67) and illicit “Xanax” (38%, n = 59) pills were frequently reported on scene; however, toxicology only identified oxycodone and alprazolam in 2 and 24 of these cases, respectively. The results of this study provide a better understanding of the fentanyl epidemic in this region creating an opportunity to promote increased awareness, shift focus to harm reduction, and aid in minimizing public health risks.  相似文献   
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The 4- Aminophenol (4-AP) colorimetric test is a fast, easy-to-use, and cost-effective presumptive assay of cannabis plant material producing different chromophores with THC-rich cannabis (blue color) and with CBD-rich cannabis (pink color). The main drawback of the 4-AP test is a brief observation window where the color rapidly changes to black, limiting the utility of the test. We now report for the first time, the identification of the product chromophores between 4-AP and CBD/THC as well as propose an explanation and a solution for the color degradation of the chromophores. The identification of the chromophores is provided by spectroscopic (UV–Vis), chromatography, and mass spectrometry (TLC and LC-QToF-MS). Oxidation of excess 4-AP (Reagent A) in the presence of NaOH (Reagent B) produces the black color observed for the previously reported 4-AP tests and reported in the literature. The adjustment of reactants concentrations and volumes of 4-AP:THC/CBD to a 1:1 ratio significantly reduces the black oxidation by-product and increases the observation window up to 2 h instead of the previously reported 5–10 min. For the first time, mass spectrometry and chromatography confirmed that the reaction of THC and CBD with 4-AP produced chromophores with m/z (M + H) = 420, consistent with proposed indophenol structures. The TLC method developed confirmed the separation between CBD and THC chromophores. The specificity of the test is also reported, showing false positive results for the presence of THC (blue color) for samples of thyme and oregano. LDA and SIMCA models showed that the optimized 4-AP procedure performs better than the previously reported 4-AP color test.  相似文献   
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While there has been much emphasis over the last decade on the science of nanotechnology and on the implications and risks of potential applications, it is now timely to increase attention to the emerging dynamics of nanotechnology commercialization. This paper examines, from a global perspective, where and how corporations are entering into nanotechnology innovation. The paper tests the proposition that a significant shift has occurred in recent years in the orientation of corporate nanotechnology activities—from research discovery to patented applications. It also examines the extent to which the character and structure of corporate nanotechnology activity by country initially reflects national innovation system characteristics and prior public research funding inputs in the stage when discovery is most emphasized. The results indicate that national innovation systems characteristics are significant factors in the commercialization shift of nanotechnology and highlight the importance of innovation system policy factors. We also observe the influence of cross-border international invention linkages, suggesting that national innovation policies also need to be open and international in orientation.  相似文献   
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