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141.
In this study we investigated the mediated influence of core self-evaluations (CSE) on employee health problems via job satisfaction and work stress, and the degree to which genetic factors explain these mediated relationships. Based on data obtained from a sample of 594 Swedish twins (114 monozygotic twin pairs and 183 dizygotic twin pairs), conventional path analysis results supported the mediated effects of CSE on employee health via job satisfaction and work stress, after controlling for conscientiousness and extraversion. Behavioral genetic analyses showed significant heritability of all four variables. Moreover, we found that the mediated relationships via job satisfaction and work stress are explained by genetic factors, such that the genetic source of job satisfaction and work stress mediates the genetic influence of CSE on health problems. These results highlight the role played by genetic factors in better understanding the relationships between CSE, work attitudes, and health outcomes. 相似文献
142.
María Fernanda Olarte Sierra Adriana Díaz Del Castillo Hernández 《Science as culture》2014,23(2):226-252
In Colombia, as in other Latin American countries, current population genetics research is based on the understanding that Colombians constitute a mestizo nation, given the admixture process that took place between Africans, Amerindians, and Europeans during colonial times. The mestizo is a pervasive category used by geneticists to conduct, organise, and publish research studies that deal with the continent's peopling process and the genetic makeup of its contemporary population(s). It is also the dominant imaginary for the Colombian population and a key nation-building ideology. By tracing how this category moves and is used across four Colombian genetics laboratories, it is possible to discern that despite its apparently clear-cut boundaries, the mestizo is contingent, contested, and flexible, allowing for multiple understandings and usages. This flexibility and multiplicity are visible in the quantification of genetic ancestry, the divisions of geographical location, and the understanding of gender. Such understandings allow one to think about a homogeneous nation (inclusive) that is simultaneously heterogeneous (exclusive); they provide multiple but not necessarily contradictory possibilities of being mestizo, allowing the coexistence of images of the nation that could otherwise seem contradictory; and they permit navigation around contested terms such as race, while simultaneously thinking of mixed races or racialised individuals. Finally, these flexible and multiple constructions of the mestizo (re)produce various subjects as ‘other’, whether they are women, the Indigenous, the black/dark, or the poor. 相似文献
143.
探讨肝素/低分子肝素诱导的重症血小板减少救治经验与规律.对2例分别使用肝素、低分子肝素后出现重症血小板减少患者发病、临床特征、实验室检查等进行分析,进一步提高该类重症病的认识,总结救治经验:严密监测,早期发现,一旦出现重症血小板减少,及时停用肝素和/或低分子肝素,换用非肝素类抗凝药;立即激素(地塞米松30mg/d)冲击治疗2天,重症血小板减少(PLT≤3×109/L)并出血者酌情输注血小板. 相似文献
144.
探讨肝素/低分子肝素诱导的重症血小板减少救治经验与规律.对2例分别使用肝素、低分子肝素后出现重症血小板减少患者发病、临床特征、实验室检查等进行分析,进一步提高该类重症病的认识,总结救治经验:严密监测,早期发现,一旦出现重症血小板减少,及时停用肝素和/或低分子肝素,换用非肝素类抗凝药;立即激素(地塞米松30mg/d)冲击治疗2天,重症血小板减少(PLT≤3×109/L)并出血者酌情输注血小板. 相似文献
145.
《European Journal of Developmental Psychology》2013,10(6):645-664
Sexual socialization refers to how, through social interaction, an individual acquires and internalizes culture-specific knowledge, values and attitudes about sexuality. Little, however, is known about how an individual's genetic characteristics modify this process, or if individuals gravitate towards specific environments according to their genetic characteristics. The aim was to explore whether adolescents' genetic predispositions modify environmental influences on peer-group sexual attitudes. Using a Finnish population-based sample of twins and their siblings (n = 9534), it was found that genetic effects influenced peer-group sexual attitudes in men (52%) and women (46%), thus offering evidence for gene–environment correlation. Men showed less restricted peer-group sexual attitudes than women. Some indications of different genes influencing environmental exposure in men and women were found. 相似文献
146.
K. Vijay Reddy 《Philosophical Magazine Letters》2013,93(7):253-260
Stacking fault tetrahedra (SFTs) are known to form during the rolling process of face-centered cubic metals and to deteriorate their structural properties. However, the atomistic mechanism of formation and destruction of SFTs during such material processing is still unclear. We have performed molecular dynamics simulations of the nanoscale cryo-rolling process for single-crystal nickel and here report the mechanism behind the formation and collapse of SFTs. It is found that SFTs are formed through dissociation of Shockley partial dislocation loops in the specimen. On the other hand, destruction of SFTs occurs under compressive stress and follows an inverse Silcox-Hirsch mechanism. 相似文献
147.
148.
Alexander V. Evteev Elena V. Levchenko Daniel P. Riley Irina V. Belova 《Philosophical Magazine Letters》2013,93(12):815-830
The kinetic reaction in a Ni-coated Al nanoparticle with equi-atomic fractions and diameter of approximately 4.5 nm is studied by means of molecular dynamics simulation, using a potential of the embedded atom type to model the interatomic interactions. First, the large driving force for the alloying of Ni and Al initiates solid state amorphization of the nanoparticle with the formation of Ni50Al50 amorphous alloy. Amorphization makes intermixing of the components much easier compared to the crystalline state. The average rate of penetration of Ni atoms can be estimated to be about two times higher than Al atoms, whilst the total rate of inter-penetration can be estimated to be of the order of 10?2 m/s. The heat of the intermixing with the formation of Ni50Al50 amorphous alloy can be estimated at approximately ?0.34 eV/at. Next, the crystallization of the Ni50Al50 amorphous alloy into B2-NiAl ordered crystal structure is observed. The heat of the crystallization can be estimated as approximately ?0.08 eV/at. Then, the B2-NiAl ordered nanoparticle melts at a temperature of approximately 1500 K. It is shown that, for the alloying reaction in the initial Ni-coated Al nanoparticle, the ignition temperature can be as low as approximately 200 K, while the adiabatic temperature for the reaction is below the melting temperature of the nanoparticle with the B2-NiAl ordered structure. 相似文献
149.
Renée R. Lajiness-O’Neill Isabelle Beaulieu Jeffrey B. Titus Alexander Asamoah Erin D. Bigler Erawati V. Bawle 《Child neuropsychology》2013,19(1):55-71
This study examined memory functioning in children and adolescents with 22q11.2 Deletion Syndrome (DS; velocardiofacial syndrome). An overall verbal better than nonverbal memory pattern was evident on the Test of Memory and Learning (TOMAL), with children with 22q11.2 DS performing significantly below their siblings and children with low average IQ but similar to children with autism on facial memory. Children with 22q11 DS also performed significantly below their siblings on tests of verbal working memory. Children with autism performed significantly poorer than the siblings of children with 22q11.2 DS only on their recall of stories. Delayed recall was significantly poorer in children with 22q11.2 DS and children with autism, compared to sibling controls. Although there were no significant group differences on tests of multiple trial verbal or visual learning, a relative weakness was noted with multiple trial visual learning in children with 22q11.2 DS and their siblings, suggesting that an alternative or interactive factor other than the deletion may account for the relatively better verbal compared to nonverbal memory abilities. Deficits in facial memory in children with both 22q11.2 DS and autism suggest disruptions in ventral temporal pathways such as between fusiform gyrus and parahippocampal/hippocampal regions whereas deficits in verbal working memory in children with 22q11.2 DS implicates dorsolateral prefrontal regions, both intimating aberrant white matter pathways. 相似文献
150.
Although attention deficit disorders are frequently diagnosed in low birth-weight children, it is not clear if attention problems are apparent in neuropsychological testing. The present study examined the performances of a regional sample of 68 children with birth weights <750 gm on several psychometric measures of attention given at early school age. Matched groups of 65 children with birth weights between 750–1499 gm and 61 term controls were also assessed. The group <750 gm performed more poorly on one attention test than did either comparison group, even when overall cognitive ability was taken into account. Performances on the attention tests were also related to academic skills and ratings of behavior. Findings confirm the hypothesis that children with birth weights <750 gm have specific attentional weaknesses and support the validity of attention tests as predictors of learning and behavior problems. 相似文献