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931.
    
In 2 experiments, the effects of mental stress on limb stiffness were investigated. The relative contribution to arm stiffness of individual muscle activity, co-contraction, muscle reflexes, and postural adjustments were examined. In each experiment, participants (N = 24, Experiment 1; N = 16, Experiment 2) held their supinated hand under a tray that they were required to return to horizontal after it had been suddenly released. Electromyographic activity in the biceps and triceps muscles was recorded, as were elbow and wrist angles and tray displacement. In Experiment 1, mental arithmetic stress was shown to lead to decreased tray displacement (i.e., increased resistance) compared with displacements under the control, unstressed condition, as well as to increased elbow flexion before tray release. In Experiment 2, the increased resistance to perturbation caused by mental stress was found to be independent of initial elbow angle, but to vary as a function of the amount of upward force exerted before tray release. The authors conclude that stress-induced increases in limb stiffness result from changes in the initial position of the elbow, specified by its angle, together with the initial force exerted by participants to counteract the mechanical perturbations.  相似文献   
932.
933.
Master narratives frame students’ historical knowledge, possibly hindering access to more historical representations. A detailed analysis of students’ historical narratives about the origins of their own nation is presented in terms of four master narrative characteristics related to the historical subject, national identification, the main theme and the nation concept. The narratives of Argentine 8th and 11th graders were analyzed to establish whether a change toward a more complex historical account occurred. The results show that the past is mostly understood in master narrative terms but in the 11th grade narratives demonstrate a more historical understanding. Only identification appears to be fairly constant across years of history learning. The results suggest that in history education first aiming at a constructivist concept of nation and then using the concept to reflect on the national historical subject and events in the narrative might help produce historical understanding of a national past.  相似文献   
934.
In this study we tested whether children from Dutch‐immigrant families are at increased risk for maltreatment, and if so, what factors could explain this risk. Three data sources from the second Netherlands Prevalence Study of Maltreatment of Youth (NPM‐2010) were used to answer these questions. First, 1127 professionals from various occupational branches (sentinels) were asked to report each child (including some background information on the child and family) for whom they suspected child maltreatment during a period of three months. Second, we included the 2010 data from the Dutch Child Protective Services and third, 1759 high school students aged 11–17 years filled out a questionnaire on their experiences of maltreatment in the past year. We found that children from traditional immigrant families with a relatively long migration history in the Netherlands (Turkish, Moroccan, Surinamese, and Antillean) and from nontraditional immigrant families (African [except Morocco], Eastern European, Central Asian, and South and Central American; often refugees) were at increased risk for child maltreatment compared to native Dutch families. However, in the professionals’ and CPS data this risk disappeared for the traditional immigrant families after correction for educational level of the parents and for step‐parenthood. Within the group of families with low education or step‐parents, the risk for child maltreatment was similar for traditional immigrant families as for native Dutch families. Nontraditional families remained at increased risk after correction for sociodemographic and family factors. In conclusion, we found that children from both traditional and nontraditional immigrant families are at increased risk for maltreatment as compared to children from native Dutch families. For the traditional immigrants this risk could partially be explained by socioeconomic status. This implies that socioeconomic factors should be taken into account when outlining policies to fight child maltreatment.  相似文献   
935.
Recently it has been reported that practicing putting with visual illusions that make the hole appear larger than it actually is leads to longer-lasting performance improvements. Interestingly, from a motor control and learning perspective, it may be possible to actually predict the opposite to occur, as facing a smaller appearing target should enforce performers to be more precise. To test this idea the authors invited participants to practice an aiming task (i.e., a marble-shooting task) with either a visual illusion that made the target appear larger or a visual illusion that made the target appear smaller. They applied a pre–post test design, included a control group training without any illusory effects and increased the amount of practice to 450 trials. In contrast to earlier reports, the results revealed that the group that trained with the visual illusion that made the target look smaller improved performance from pre- to posttest, whereas the group practicing with visual illusions that made the target appear larger did not show any improvements. Notably, also the control group improved from pre- to posttest. The authors conclude that more research is needed to improve our understanding of whether and how visual illusions may be useful training tools for sport skill learning.  相似文献   
936.
    
The relative contribution of child and parent trait anxiety on paternal and maternal controlling behaviour was examined. Thirty-seven children, aged 8–11 years, completed two difficult Tangram puzzles, one with their father and one with their mother. Videotapes of the parent–child interactions were rated on parental control and child dependent and withdrawn behaviour. Results indicated that, opposite to expectations, higher mother and father trait anxiety was associated with lower levels of parental control, and that the relation between parent trait anxiety and parental control was curvilinear. Furthermore, a significant stronger effect between child trait anxiety and parental control was found for boys than for girls. Moreover, more child withdrawal during the parent–child interaction was related to more parental control. The findings offer new insights, which may guide future theories on child and parent anxiety and parental control. Specifically, the role of parent and child gender need further conceptualisation and research.  相似文献   
937.
    
Prior definitions and empirical research do not distinguish responses to transgressions driven by feelings of revenge from responses to transgressions driven by feelings of anger. We used autobiographical recalls to examine differences between vengeful and anger-driven responses. Our findings revealed that vengeful responses are not the same as anger-driven responses. Compared to anger-driven responses, vengeful responses resulted more from offences that induce a self-threat, which elicited more intense negative self-conscious emotions and more rumination. Moreover, compared to anger-driven responses, vengeful responses consisted more of behaviours that induced a self-threat to the other person, were motivated more by intrapersonal goals, were more delayed, elicited more positive emotions and resulted in less relationship restoration. Together, these findings suggest that more so than anger-driven responses, vengeance is self-focused.  相似文献   
938.
    
Integrating insights from research examining the effect of being seen through the lens of stereotypes on academic performance and the social identity perspective, we examine the effect of perceived affirmative action admission at college entry on academic performance at the end of the first year. We propose that stereotype threat plays a crucial moderating role in determining when performance is affected. A longitudinal study of Black and Latino students at a large multiethnic university showed that perceptions of affirmative action admission negatively affected achievement among high stereotype-threatened individuals but not among low stereotype-threatened individuals. Furthermore, the results show that stereotype threat can have its effects because of concerns for the self (personal identity stereotype threat) or because of concerns for the group (social identity stereotype threat). As expected, social identity stereotype threat negatively affected the performance of individuals high in ethnic identification, whereas personal identity stereotype threat negatively affected the performance of individuals low in ethnic identification.  相似文献   
939.
    
Abstract

This paper considers Tabensky’s method of critical introspection, and in particular the conception of personhood that informs it. By interrogating the lives of pure hedonism, divinity and immortality from our already existing conception of personhood, Tabensky argues that such lives are incompatible with what it is to be a person, and desiring to live them is therefore irrational. Concentrating on the example of immortality, I argue that, while there are undoubtedly disadvantages associated with the immortal life, these are contingent rather than essential to the notion of being a person. In fact, we have very little idea of the boundaries of that concept. The paper concludes by looking at the consequences of Tabensky’s approach for issues surrounding moral vision and improvement, and new technologies of the person.  相似文献   
940.
    
Abstract

We argue that separation-survivability is a significant developmental fetal milestone beyond which abortion is only rarely and exceptionally morally justifiable. Secondly, we argue that the continuous nature of prenatal development, and simultaneous parallel development and actuation of intrinsic and contingent potentiality that eventually results in the development of a person capable of moral thoughts and deeds, implies continuously incremental moral significance. We propose that the moral justifiability of each instance of non-therapeutic pre-viable termination should be the product of an internal dialectic or “moral enquiry”. Arguments should be of increasing power in order to trump the sliding-scale increase in prenatal moral significance. We agree that sentience is morally significant, but argue that survivability is of predominant importance, since human beings who have the potentiality of separate, relatively independent lives, should, normally, be allowed to continue living. We argue for a moderate position on abortion.  相似文献   
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