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931.
The United States has made a significant effort and investment in STEM education, yet the size and the composition of the STEM workforce continues to fail to meet demand. It is thus important to understand the barriers and factors that influence individual educational and career choices. In this article, we conduct a literature review of the current knowledge surrounding individual and gender differences in STEM educational and career choices, using expectancy–value theory as a guiding framework. The overarching goal of this paper is to provide both a well-defined theoretical framework and complementary empirical evidence for linking specific sociocultural, contextual, biological, and psychological factors to individual and gender differences in STEM interests and choices. Knowledge gained through this review will eventually guide future research and interventions designed to enhance individual motivation and capacity to pursue STEM careers, particularly for females who are interested in STEM but may be constrained by misinformation or stereotypes.  相似文献   
932.
《Women & Therapy》2013,36(3-4):123-132
Abstract

Preparation for their changing roles in family and society, as well as readying their intimate space for the arrival of an infant, totally engage expectant parents. Miscarriage or stillbirth may bring on a grief storm that strips away many tender roots and branches of new life in the community that the parents have been nurturing. Creation and participation in a grief ritual can bring the grieving parents to a healing resolution. This article describes the healing efficacy of ritual, its elements, and how a compassionate therapist can create one in collaboration with grieving clients.  相似文献   
933.
Parietal cortical areas are involved in sensori-motor transformations for their respective contralateral hemifield/body. When arms of the subjects are crossed while their gaze is fixed straight ahead, vision of the hand is processed by the hemisphere ipsilateral to the arm position and proprioception of the arm by the contralateral hemisphere. It induces interhemispheric transfer and remapping. Our objective was to investigate whether a single pulse TMS applied to the left parietal cortical area would disturb interhemispheric remapping in a similar case, and would increase a simple reaction time (RT) with respect to a control single pulse TMS applied to the frontal cortical area. Two LED were superimposed and located in front of the subjects on the saggital axis. Subjects were asked to carefully fixate on these LED during each trial. The lighting of the red LED was used as a warning signal. Following the green one was illuminated after a variable delay and served as a go-signal. The hand for the response was determined before the start of each trial. TMS was applied to the left parietal, the left frontal cortical areas, or not applied to the subject. Results revealed that: (1) Irrespective of its location, single pulse TMS induced a non-specific effect similar to a startle reflex and reduced RT substantially (15 ms on average) with respect to a control condition without TMS (mean value = 153 ms). (2) Irrespective of TMS, RT were shorter when the right or the left hand was positioned in the right visual hemi-field (i.e. normal and crossed positions respectively). (3) Finally, RT increased when single pulse TMS was applied to the left parietal area and when hands were crossed irrespective of which hand was used. We concluded that interhemispheric sensori-motor remapping was disrupted by a single pulse TMS that was applied to the left parietal cortex. This effect was also combined with some visual attention directed towards the hand located on the right visual hemi-field.  相似文献   
934.
Unlike prospective time perception paradigms, in which participants are aware that they have to estimate forthcoming time, little is known about retrospective time perception in normal aging and Alzheimer’s disease (AD). Our paper addresses this shortcoming by comparing prospective and retrospective time estimation in younger adults, older adults, and AD patients. In four prospective tasks (lasting 30 s, 60 s, 90 s, or 120 s) participants were asked to read a series of numbers and to provide a verbal estimation of the reading time. In four other retrospective tasks, they were not informed about time judgment until they were asked to provide a verbal estimation of four elapsed time intervals (lasting 30 s, 60 s, 90 s, or 120 s). AD participants gave shorter verbal time estimations than older adults and younger participants did, suggesting that time is perceived to pass quickly in these patients. For all participants, the duration of the retrospective tasks was underestimated as compared to the prospective tasks and both estimations were shorter than the real time interval. Prospective time estimation was further correlated with mental time travel, as measured with the Remember/Know paradigm. Mental time travel was even higher correlated with retrospective time estimation. Our findings shed light on the relationship between time perception and the ability to mentally project oneself into time, two skills contributing to human memory functioning. Finally, time perception deficits, as observed in AD patients, can be interpreted in terms of dramatic changes occurring in frontal lobes and hippocampus.  相似文献   
935.
ABSTRACT

Careers provision for young people in the UK is being re-formulated on the basis of a central role for career websites but this policy is based on unproven assumptions about their value. In this article we consider the use and impact of the two main career websites in Scotland on pupils' career management skills. We found that pupils at risk of not achieving positive post-school destinations were less likely to use the websites, as were minority ethnic pupils. Although similar in functions, the two websites differed in their effect: one had no impact while the other impacted on only one aspect of pupils' career management skills. Careers policy needs to be informed by more extensive research on career websites.  相似文献   
936.
Being imitated has a wide range of pro‐social effects, but it is not clear how these effects are mediated. Naturalistic studies of the effects of being imitated have not established whether pro‐social outcomes are due to the similarity and/or the contingency between the movements performed by the actor and those of the imitator. Similarity is often assumed to be the active ingredient, but we hypothesized that contingency might also be important, as it produces positive affect in infants and can be detected by phylogenetically ancient mechanisms of associative learning. We manipulated similarity and contingency between performed and observed actions in a computerized task. Similarity had no positive effects; however, contingency resulted in greater enjoyment of the task, reported closeness to others, and helping behavior. These results suggest that the pro‐social effects of being imitated may rely on associative mechanisms.  相似文献   
937.
双酚A (bisphenol, BPA)是一种广泛存在的环境内分泌干扰物,它可与雌激素受体结合干扰内源性雌激素对中枢神经系统的调控作用。本研究通过将10周龄小鼠灌胃染毒BPA (0.4、4、40 mg/kg/day)3个月,研究长期BPA暴露对成年小鼠记忆行为和突触可塑性的影响。开场行为测试结果表明, BPA (0.4、4、40 mg/kg/day)增加雄性的站立次数和理毛频率, BPA (4 mg/kg/day)却显著减少雌鼠的站立次数。水迷宫和被动回避行为模型检测显示, BPA主要损伤雄鼠的空间学习记忆和被动回避记忆。通过制备海马CA1区超薄切片后,电镜观测发现, BPA (0.4、40 mg/kg/day)暴露降低雄鼠海马CA1区突触数密度,缩短雄鼠突触前活性带长度,减小雄鼠突触后致密体(PSD)厚度,增加雄鼠突触间隙宽度。进一步用Western blot方法检测突触前、后的标志性蛋白Synapsin I和PSD95以及兴奋性氨基酸NMDA受体NR1亚基和AMPA受体GluR1亚基蛋白的表达,发现BPA暴露致雄鼠Synapsin I、PSD95、NR1蛋白表达水平下调。而BPA对雌鼠的记忆行为、突触形态、突触蛋白和受体蛋白均没有明显作用。以上结果提示长期B PA暴露性别特异性地影响成年小鼠的活动性和探究行为,损伤雄鼠的学习记忆,这些作用可能通过下调突触蛋白和NMDA受体的表达而负性影响突触结构可塑性,最终影响雄鼠的学习记忆功能。  相似文献   
938.
Thomas F. Tracy 《Zygon》2013,48(2):454-465
When Darwin's theory of natural selection threatened to put Paley's Designer out of a job, one response was to reemploy God as the author of the evolutionary process itself. This idea requires an account of how God might be understood to act in biological history. I approach this question in two stages: first, by considering God's action as creator of the world as a whole, and second, by exploring the idea of particular divine action in the course of evolution. As creator ex nihilo God acts directly in every event as its sustaining ground. Because God structures the world as a lawful order of natural causes, God also acts indirectly by means of creatures. More controversially, God might act directly within the world to affect the course of events; this action need not take the form of a miraculous intervention, if the natural order includes the right sort of indeterministic chance. In each of these ways God's purposes can shape evolutionary processes.  相似文献   
939.
This article reviews, and offers supportive reflections on, the main points of Ernan McMullin's provocative 1998 article, “Cosmic Purpose and the Contingency of Human Evolution,’’ reprinted in this issue of Zygon. In it he addresses the important science‐theology issue of how the Creator's purpose and intention to assure the emergence of human beings is consonant with the radical contingency of the evolutionary process. After discussing cosmic and biological evolution and critically summarizing recent solutions to this question by Keith Ward, John Polkinghorne, Arthur Peacocke, Alvin Plantinga, and others, who presuppose in different ways that God is subject to time, McMullin compellingly argues for the traditional position, that God is unconditioned by time, and this enables God to work purposefully through contingency, randomness, and chance just as easily as through law‐like regularity.  相似文献   
940.
Remembering persisting objects over occlusion is critical to representing a stable environment. Infants remember hidden objects at multiple locations and can update their representation of a hidden array when an object is added or subtracted. However, the factors influencing these updating abilities have received little systematic exploration. Here we examined the flexibility of infants’ ability to update object representations. We tested 11-month-olds in a looking-time task in which objects were added to or subtracted from two hidden arrays. Across five experiments, infants successfully updated their representations of hidden arrays when the updating occurred successively at one array before beginning at the other. But when updating required alternating between two arrays, infants failed. However, simply connecting the two arrays with a thin strip of foam-core led infants to succeed. Our results suggest that infants’ construal of an event strongly affects their ability to update memory representations of hidden objects. When construing an event as containing multiple updates to the same array, infants succeed, but when construing the event as requiring the revisiting and updating of previously attended arrays, infants fail.  相似文献   
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