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81.
The effects of crystallization on the electron work function and corrosion resistance of Zr65Al7.5Cu17.5Ni10 amorphous alloys have been studied. The single-phase amorphous alloy exhibits a better corrosion resistance and has a higher work function than the partially and fully crystallized alloys with the same composition. The close relationship between corrosion resistance and work function indicates that the Kelvin probe technique can be a powerful tool for characterizing the corrosion behaviour of amorphous alloy on an electronic level.  相似文献   
82.
Theorists have long suggested that joint caregiver–child reminiscence is functional, in that it is useful, adaptive, and can be utilised to achieve a variety of goals in everyday life. In the present study we investigated caregiver reports of the functions of joint reminiscence across early childhood. Participants were 203 parents or other guardians of 2–6-year-old children. Caregivers completed the Caregiver–child Reminiscence Scale (CRS) designed to tap functions of joint reminiscence. Our results indicated that caregivers reported frequently talking about past experiences with their children. Exploratory factor analysis revealed seven functions of joint reminiscence: Emotion Regulation, Directive, Positive Emotionality, Individual Self in Relation to Others, Conversation, Cognitive Skills, and Peer Relationships. Although some of these functions map directly onto adult-like functions outlined in the theoretical literature, others are unique to the context of joint reminiscence and reflect developmental goals of the early childhood period.  相似文献   
83.
ABSTRACT

Cultural differences in autobiographical memory characteristics and function have often been presumed to be associated with different cultural beliefs related to the self. The current research aimed to investigate whether self-construal mediated the relationship between cultural group and the characteristics and functional use of autobiographical memory. Caucasian Australians (n?=?71) and Malay Malaysians (n?=?50) completed an online questionnaire that included the Self-Defining Memory task, the Thinking About Life Experiences Revised Questionnaire and the Self Construal Scale. As expected, the Australian group provided longer, more autonomously oriented, specific memories than the Malay group. However, contrary to our predictions, self-construal did not mediate the relationships between cultural group and memory characteristics. The Malay group reported more frequently using autobiographical memories for self-continuity than the Australian group. Finally, there was support for an indirect pathway between cultural group and use of autobiographical memories for self-continuity and social-bonding through self-construal (i.e. independent self relative to interdependent self). The findings highlight the importance of explicitly examining values assumed to be associated with autobiographical remembering, and relating these values to memory characteristics and function.  相似文献   
84.
ABSTRACT

Grounded in the ecological approach, research has charted several adaptive functions of autobiographical remembering. Each represents a rather different psychosocial domain (i.e., self, social, directive). The goal of this research was to determine the contributions of each of a set of variables, controlling for all others, in predicting use of autobiographical memory to serve each specific function. In two studies, participants (N?=?100; N?=?195) rated frequency of functional use of specific event memories and completed a brief battery of memory-related measures. Most Study One results were replicated in Study Two. Self-relevance of memories was related to their functional use regardless of domain. Each function was also, however, predicted by a unique set of variables consistent with its use in a given psychosocial domain. Findings emphasise how a combination of factors come into play to allow humans to use autobiographical memory to serve various different functions in navigating daily life.  相似文献   
85.
长期以来,对心衰和心衰机制的认识一直存在争议,所以心衰的治疗一直是国内外心血管领域中的一个挑战.为了澄清心衰机制的内涵,本文用弗兰克-斯塔灵定律以及能量守恒定律作为重建心脏理论以及心衰机制的依据,论证了心脏的做功是从动能向势能,又从势能向动能的转换过程.并根据临床事实等来证实心脏舒张是在作功,与收缩期作功是等同的.没有心脏的舒张就没有心脏的收缩,心脏功能下降实际上是舒张与收缩功能同时的下降.不存在有收缩功能正常的舒张功能下降.心功能的判定标准不能采用射血分数,而应该采取能量消耗的定量方法来测定.  相似文献   
86.
In this article the authors compared chimpanzees’ executive function with that of children. They developed a nonverbal dimensional change card sorting task, which indexed the development of executive function. Three pairs of mother and offspring chimpanzees and 30 typically developed 5-year-old children were presented with 2 target stimuli and a test stimulus comprising 2 dimensions (size and shape) on a display; they were required to sort the test stimulus according to 1 dimension (e.g., shape). After 5 consecutive correct trials, the participants had to sort the test stimulus according to the other dimension (e.g., size). The results showed that the chimpanzees often failed to sort the test stimuli according to the first and reversed dimensions. On the other hand, the children were correctly able to use both dimensions. These results indicate that chimpanzees may have less developed executive skills than children.  相似文献   
87.
This study examined motor skill learning using a weight-bearing and cognitive-motor dual-task that incorporated unexpected perturbations and measurements of cognitive function. Forty young and 24 older adults performed a single-limb weight bearing task with novel speed, resistance, and cognitive dual task conditions to assess motor skill acquisition, retention and transfer. Subjects performed a cognitive dual task: summing letters in one color/orientation (simple) or two colors/orientations (complex). Increased cognitive load diminished the rate of skill acquisition, decreased transfer to new conditions, and increased error rate during an unexpected perturbation; however, young adults had a dual-task benefit from cognitive load. Executive function predicted 80% of the variability in dual-task performance. Although initial learning of a weight-bearing cognitive-motor dual-task was poor, longer term goals of improved dual-task effect and retention emerged.  相似文献   
88.
We investigated the association between adolescent depressive symptoms and components of executive functioning (EF), including planning (Tower of London), set-shifting (Wisconsin Card Sorting Task), and inhibition (Stop Signal Task) in a community sample of 12–14 year olds. Further, EF was tested as a moderator of motivation (as operationalized by revised Reinforcement Sensitivity Theory) effects on depressive symptoms. Results suggested that planning ability was associated with depressive symptoms. Furthermore, planning ability moderated the relationship between motivation (fight-flight–freeze system; FFFS) and depressive symptoms, such that among adolescents with poor planning ability the FFFS positively predicted depressive symptoms, but among adolescents with strong planning ability the FFFS negatively predicted depressive symptoms. Neither set-shifting nor inhibition were associated with depressive symptoms. Findings highlight the need to consider multiple components of EF and to integrate motivational and executive dysfunction models to the study of depression.  相似文献   
89.
People constantly face the need to choose one option from among many, such as when selecting words to express a thought. Selecting between many options can be difficult for anyone, and can feel overwhelming for individuals with elevated anxiety. The current study demonstrates that anxiety is associated with impaired selection across three different verbal tasks, and tests the specificity of this finding to anxiety. Anxiety and depression frequently co-occur; thus, it might be assumed that they would demonstrate similar associations with selection, although they also have distinct profiles of symptoms, neuroanatomy and neurochemistry. Here, we report for the first time that anxiety and depressive symptoms counter-intuitively have opposite effects on selection among competing options. Specifically, whereas anxiety symptoms are associated with impairments in verbal selection, depressive symptoms are associated with better selection performance. Implications for understanding the mechanisms of anxiety, depression and selection are discussed.  相似文献   
90.
Because the definition of behavior changes as our understanding of behavior changes, giving a final definition is impossible. One can, however, rule out some possibilities and propose some others based on what we currently know. Behavior is not simply movement, but must be defined by its function. Also, our understanding of behavior must agree with evolutionary theory. I suggest 4 basic principles: (a) only whole organisms behave; (b) behavior is purposive; (c) behavior takes time; and (d) behavior is choice. Saying that parts of an organism behave is nonsense, and, moreover, evolutionary theory explains the existence of organisms mainly through their adaptive behavior. Behavior is purposive in that behavior is shaped by its consequences, through an organism''s lifetime or through interactions with the environment across many generations of natural selection. Behavior takes time in that behavior is interaction with the environment that cannot take place at a moment. Moreover, at a moment in time, one cannot definitely identify the function of behavior. Identification of an activity requires a span of time. Behavior is choice in the sense that a suitable span of time always includes time spent in more than 1 activity. Activities include parts that are themselves activities on a smaller time scale and compete for time. Thus, behavior constitutes time allocation. An accounting problem arises whenever any behavior is attributed to multiple consequences. In the molar multiscale view, this raises the question of whether 2 activities can occur at the same time. The question remains open.  相似文献   
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