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191.
Jonathan Zimmerman 《The History of the Family》2013,18(1):31-47
The article uses love letters to re-analyze current notions about men and romantic love in the 1950s. Examining advice literature as well as evidence from fiction and film, European and American historians generally describe the 1950s as an era of emotional “formalization” or suppression. A newly analyzed set of 300 love letters by over a dozen American men suggests a much more nuanced view. Some of their letters support scholarly accounts of “remasculinization” in the 1950s, displaying a hard-boiled, tough-guy quality to compensate for challenges to men's roles in the workplace and family. Other men, however, openly expressed their passions, fears, and other feelings. Since these letters were written to the author's mother, they also suggest new potentials and opportunities for “personal” research. Given the paucity of love correspondence in postwar archives, professional historians might find personal collections useful evidence to study the character and dilemmas of modern romance. 相似文献
192.
《Science & justice》2022,62(4):471-475
Insects present on or near decomposing bodies are collected by forensic entomologists and used to estimate the post-mortem interval. Drugs metabolized by a person before death may affect the rate of development of insects feeding on the corpse. This study aimed to determine the effects of cocaine and heroin main metabolites on the development rate of the Calliphora vomitoria (Diptera: Calliphoridae) and their implications on minimum post-mortem interval determination. Groups of 250 eggs each were placed into four separate pots of 150 g of minced pork meat being either un-spiked, or spiked with benzoylecgonine, morphine, or a combination of both. Larval length (mm) and weight (mg) measurements were taken twice daily and the rate of development of the insects’ life cycle was monitored until eclosion. Results show that cocaine-fed larvae developed less in length and weight than the control group. Heroin-fed larvae showed a more fluctuating pattern, being smaller and lighter than the control group for most of their larval cycle, but overtaking them in both parameters towards pupation. Combination-fed larvae seemed to favour the effects of cocaine. The three conditions also had a significant impact on the length of the insects’ life cycle. Cocaine and drug combination treatments increased the length of the second and third instar stages, but led to the shortening of pupation and accelerated eclosion. Conversely, heroin treatment led to lengthier pupation. Interestingly, the effects of the drug combination seemed to mirror more precisely those of cocaine.These findings indicate that both cocaine and heroin, singularly and in combination, have sizable effects on blowflies’ development rates, potentially biasing post-mortem interval estimations. 相似文献
193.
Short tandem repeats (STRs) incur in length mutations that involve the loss or gain of repeats. STR mutation rates are usually estimated considering the rates of observed Mendelian incompatibilities in one generation familial configurations. When considering multistep mutations, for the autosomal and X-chromosomal modes of genetic transmission, underestimations are inevitable when using this approach (MIA), due to the occurrence of mutational events deceptively perceived as involving fewer steps. The rate of this occurrence depends on the mode of genetic transmission considered, the parental origin of the mutation, the type of familial configuration considered, and the genotypic background of the progenitor(s). MIA biases were weighted and compared for the diploid and haplodiploid modes of transmission, using familial genotypic configurations (parent(s)-child duos and trios) generated resorting to Python™ and real population databases from Norway, Somalia, and Spain for 10 Aut-STRs and Argentina, Eastern Asia, and Northern Europe for 12 X-STRs. One two- or one three-step mutation was simulated in each of the 1,000,000 familial configurations. The frequency with which mutations could be interpreted as involving fewer steps, when the most parsimonious reasoning is employed, was computed. Results showed that the magnitude and type of biases depend on the type of familial data and the genetic mode of transmission considered, being higher in duos than in trios, both in autosomes and the X chromosome. Indeed, whether X- or Aut-STRs are analyzed, trios generally provide better estimates and should be favored over duos. The pooling of the two types of data is not advised. The greater the number of steps involved in the mutation, the worst the estimates obtained. In X-chromosomal analyzes, trios with a paternal mutation presented the best estimates and mother-daughter duos the worst; mother-son duos showed similar estimates to trios when a maternal mutation was considered. 相似文献