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61.
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   
62.
In this study, participants read stories describing emotional episodes with either a positive or negative valence (Experiment 1). Following each story, participants were exposed to short sentences referring to the protagonist, and the event-related potential (ERP) for each sentence's last word was recorded. Some sentences described the protagonist's emotion, either consistent or inconsistent with the story; others were neutral; and others involved a semantically anomalous word. Inconsistent emotions were found to elicit larger N100/P200 and N400 than consistent emotions. However, when participants were exposed to the same critical sentences in a control experiment (Experiment 2) in which the stories had been removed, emotional consistency effects disappeared in all ERP components, demonstrating that these effects were discourse-level phenomena. By contrast, the ordinary N400 effect for locally anomalous words in the sentence was obtained both with and without story context. In conclusion, reading stories describing events with emotional significance determines strong and very early anticipations of an emotional word.  相似文献   
63.
A key aim in biology and psychology is to identify fundamental principles underpinning the behavior of animals, including humans. Analyses of human language and the behavior of a range of non‐human animal species have provided evidence for a common pattern underlying diverse behavioral phenomena: Words follow Zipf's law of brevity (the tendency of more frequently used words to be shorter), and conformity to this general pattern has been seen in the behavior of a number of other animals. It has been argued that the presence of this law is a sign of efficient coding in the information theoretic sense. However, no strong direct connection has been demonstrated between the law and compression, the information theoretic principle of minimizing the expected length of a code. Here, we show that minimizing the expected code length implies that the length of a word cannot increase as its frequency increases. Furthermore, we show that the mean code length or duration is significantly small in human language, and also in the behavior of other species in all cases where agreement with the law of brevity has been found. We argue that compression is a general principle of animal behavior that reflects selection for efficiency of coding.  相似文献   
64.
ABSTRACT

This work aims to verify if Fe atoms coming from balls and jars enter into solid solution of Cu-Mo powders during mechanical alloying. The powders were milled and its structure and composition were characterised by scanning and transmission electron microscopy, and X-ray diffraction. Gibbs free of mixing values for Cu-Mo-Fe system were calculated using the Miedema’s model and showed that Cu-rich corner exhibit smallest energy values (<10?kJ?mol?1). The observed coherency relation Cu(111) || Mo(101) || Fe(101) confirmed formation of solid solution. Fe atoms have entered in solid solution with Cu and Mo and do not remain as particles of second phase.  相似文献   
65.
There is disagreement among researchers about the distinction between dynamic and static spatial performance. Given that dynamic spatial performance is supposed to be important for some occupations, such as air traffic control (ATC), it is germane to have evidence about the likelihood of that distinction. In the present study, a battery of printed static spatial and reasoning tests were applied to 480 applicants for an ATC training course. Two dynamic spatial tests were also applied. Confirmatory factor analyses were performed for testing three models. In Model A, static and dynamic spatial tests were grouped, whereas in Model B, spatial tests were separated according to their static or dynamic character, and in Model C, spatial tests were segregated according to the construct they tapped (visualization or spatial relations). The authors found that Model B, which distinguished static and dynamic spatial tests, showed the best fit. They also discuss some implications of the findings.  相似文献   
66.
The aims of the present study were twofold: assessing the prevalence and intensity of post‐traumatic stress disorder (PTSD) symptoms in victims of bullying, and exploring whether victims of bullying differ in their basic assumptions compared to a control group. A total of 183 victims of bullying and 183 control group participants took part in the research. The results showed that 42.6% of the total sample met all DSM‐IV‐TR criteria for PTSD, whereas 54.1% did not fulfill the A1 criterion. Post‐traumatic symptoms were more prevalent among women (49%), as compared to men (35.3%). Furthermore, victims showed significantly more negative beliefs about the world, the people, and themselves, compared to their non‐bullied controls. These results fit well with cognitive theory of trauma.  相似文献   
67.
The aim of this study was to examine the comorbidity between the SCARED anxiety factors and depressive symptoms in 8-12-year-old children. Participants were 792 girls and 715 boys, who completed: the 41-ítem version of the Screen for Child Anxiety Related Emotional Disorder (SCARED), the Children's Depression Inventory (CDI) and a Socio-demographic questionnaire. Of the sample, 47% showed anxiety symptoms and 11.5% showed depressive symptoms. Heterotypic comorbidity was 82% in children at risk of depression and 20% in children at risk of anxiety. Homotypic Comorbidity between anxiety factors was 87%. Homotypic comorbidity and heterotypic comorbidity were high; their early detection will prevent the continuity of an anxious disorder and the development of depression.  相似文献   
68.
We studied the effect of emotion generated by IAPS (International Affective Picture System) pictures on incidental recognition of these pictures for short retention periods (15 min). Memorization distraction tasks and reaction time tasks were used together with short exposure times (2 seconds per picture) in order to prevent a high recognition rate that would impede testing for the effect of emotion on discrimination parameters (A′) and response bias (B′′D) (ceiling effect). We used 80 pictures representing the medium and high levels of two-dimensional emotional space. The results showed greater discrimination and a more conservative response style to unpleasant and medium arousal level pictures. These pictures produced higher confidence and lower response times in the recognition phase. The results can be explained by the negative content of the pictures and activation level effects on attentional processing and memory, and can be interpreted as a phenomenon that is evolutionarily adaptive.  相似文献   
69.
The aim of this trial has been to determine the efficacy of a group memory training method. The experimental group was compared to a placebo group (health education) or to a control group (waiting list). Forty‐five adults between the ages of 60 and 70 years (M = 66.9) were recruited by placing notices in senior citizen community centres, which encouraged people with memory problems to participate in the study. Data were collected at baseline, 1 week, and 6 months after the intervention. The efficacy of the training was evaluated by measures of objective and subjective everyday memory performance. After intervention, the experimental group participants showed an increase in objective memory performance (d = 1.95). The effect size was even higher at 6 months after intervention (d = 2.88). Further, their subjective experience related to everyday memory slips decreased (d = ?0.52). The memory training method was effective in improving everyday memory in older people with some cognitive decline. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
70.
This study examined the impact of self-referential information at early stages of emotional word processing using an affective masked-priming paradigm in which positive (e.g, espetacular[awesome]) and negative (e.g., horrível[awful]) trait-adjectives were preceded by briefly primes that could be self-related (Eu sou[I am]), other-related (Ela é[She is]), or a control (%%%%%). Trait-adjectives were selected from female norms and only females participants were used to control for sex differences. Results showed that positive words were categorised faster when preceded by self-related primes than by other-related primes, though not control primes. Negative trait-adjectives were not modulated by the type of prime, even though participants were slower when they were preceded by other-related than by control primes. These findings demonstrate that taking the other-perspective entails a cost, and that the amount of priming produced by self-related and control primes was virtually the same, thus suggesting that assuming the self-perspective is a cognitively effortless process.  相似文献   
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