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331.
Since the 1990s, inter-provincial female migration for marriage has become important in central and eastern rural China. Using survey data from X County in rural Anhui Province, we explore the arrangement of inter-provincial marriages, as well as the characteristics of husbands and wives, marital satisfaction and marital stability for these marriages. We find that inter-provincial marriage is an important option for local men to respond to the marriage squeeze and the increasing expense of marriage. It helps to relieve the shortage of marriageable women in the local marriage market. Because this kind of marriage is based on economic exchange, but not affection, it is often subject to a higher risk of marriage instability, and can lead to such illegal behaviors as marriage fraud and mercenary marriage. 相似文献
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Sudhir K. Sinha PhD Hiromi Brown PhD Hailey Holt BS Mah-ro Khan MS FS Joanne B. Sgueglia BA Gina Murphy MS 《Journal of forensic sciences》2023,68(3):1020-1035
Forensic casework samples often include human hairs, teeth, and bones. Hairs with roots are routinely processed for DNA analysis, while rootless hairs are either not tested or processed using mitochondrial DNA. Bones and teeth are submitted for human remains identifications for missing persons and mass disaster cases. DNA extraction from these low templates and degraded samples is challenging. The new InnoXtract DNA extraction method utilizes magnetic beads that are optimized to bind small DNA fragments, as small as 100 base pairs, to purify high-yield DNA from compromised samples. This validation study evaluates InnoXtract's ability to obtain amplifiable DNA from samples such as rootless hairs and skeletal remains. Studies performed include sensitivity, stability, repeatability, reproducibility, non-probative samples, and comparison to standard organic extractions. Sensitivity studies demonstrate average yield recoveries ranging from 53% to 100% and 73% to 85% for the InnoXtract hair and bone methods, respectively. Studies demonstrate consistent results across a range of sample types, such as insulted and un-insulted bone and teeth, as well as hair shafts from donors of various ages, gender, race, and hair characteristics. The InnoXtract bone method outperformed organic extraction. The method was successfully automated on a MagMAX™ Express-96, with recoveries over 70% relative to the manual version. InnoXtract has the potential as an automated high-throughput, high-yield bone extraction method with 6 h of total extraction time for up to 96 samples. The validation study results demonstrate that the InnoXtract kits produce high-yield and high-quality DNA from compromised bone, teeth, and hair shaft samples. 相似文献
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Two six-shot suicides are reported that occurred in adjoining counties in Ohio eleven-and-one-half weeks apart. There is no indication of any connection between victims, and it is doubtful that the second individual knew of the first death since there was no news media coverage of the first death. The most significant points of commonality between the two cases are the location of the gunshot wounds (anterior chest and upper abdomen) and the responses of disbelief from those outside the medicolegal professions. Knowledge of such cases with a high number of shots and more than one fatal wound can assist death investigators in confronting similar cases. 相似文献
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Unconjugated morphine in blood by radioimmunoassay and gas chromatography/mass spectrometry 总被引:1,自引:0,他引:1
Morphine, the active metabolite of heroin, is rapidly inactivated by glucuronidation at the 3 carbon. Unconjugated (pharmacologically active) morphine was measured in postmortem blood by radioimmunoassay using an antibody-coated tube kit. The kit shows less than 0.2% cross-reactivity with codeine and morphine-glucuronide. Unconjugated morphine concentrations were confirmed by gas chromatography/mass spectrometry (GC/MS) using deuterated morphine as the internal standard. The blood was precipitated with 10% trichloroacetic acid (TCA) and concentrated hydrochloric acid (HCl), centrifuged, and decanted. The supernatant was then either diluted (unhydrolyzed) or heated to 100 degrees C, 30 min (hydrolyzed), followed by a wash with 4:1 chloroform:isopropranol. The upper aqueous layer was then saturated with sodium bicarbonate (NaHCO3) and extracted with 4:1 chloroform:isopropranol. The organic layer was evaporated, derivatized with trifluoroacetic anhydride (TFA), and analyzed by selected ion monitoring (SIM) GC/MS. Comparison of the results for unconjugated morphine by radioimmunoassay and unhydrolyzed morphine by GC/MS gave a correlation coefficient of r = 0.98, n = 100. Unconjugated morphine ranged from 0 to 100% of total morphine with a mean of 42%, n = 200, for heroin or morphine involved deaths. Review of 56 putative rapid deaths gave a mean of 68% unconjugated morphine with a range of 26 to 100%. The ratio of unconjugated to total morphine was found to be stable in postmortem blood after more than a year of storage at room temperature, within the precision of the method. 相似文献
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