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101.
Infants under 7 months of age fail to reach behind an occluding screen to retrieve a desired toy even though they possess sufficient motor skills to do so. However, even by 3.5 months of age they show surprise if the solidity of the hidden toy is violated, suggesting that they know that the hidden toy still exists. We describe a connectionist model that learns to predict the position of objects and to initiate a response towards these objects. The model embodies the dual-route principle of object information processing characteristic of the cortex. One route develops a spatially invariant surface feature representation of the object whereas the other route develops a feature blind spatial–temporal representation of the object. The model provides an account of the developmental lag between infants’ knowledge of hidden objects and their ability to demonstrate that knowledge in an active retrieval task, in terms of the need to integrate information across multiple object representations using (associative) connectionist learning algorithms. Finally, the model predicts the presence of an early dissociation between infants’ ability to use surface features (e.g. colour) and spatial–temporal features (e.g. position) when reasoning about hidden objects. Evidence supporting this prediction has now been reported.  相似文献   
102.
A modified version of Caplan's Job Stress Questionnaire (JSQ) was administered to 169 male and 56 female entrepreneurs. Entrepreneurs were found to have higher levels of stress associated with workload than with role ambiguity and underutilization of skills. Compared to scores reported previously for various occupational categories, the entrepreneurs scored significantly higher than did white collar, blue collar, and professional groups on the workload scale and significantly lower on scales measuring role ambiguity and under-utilization of skills. These results may be due to the nature of entrepreneurial activity, which is often characterized by heavy workloads, long hours, and a self-established role in the organization. Additionally, the factorial composition of the JSQ and its internal consistency were examined. Evidence of convergent and discriminant validity at the item and subscale level confirmed the a priori dimensions of the JSQ, although the internal consistency of the scales were low to moderate. The need for various improvements in the measurement of occupational stress is briefly discussed.  相似文献   
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104.
The Afrocentric model is an approach to identify problems and develop strategies to enhance the sense of belonging, identity, and control in African-American females.  相似文献   
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106.
The purpose of this study was to examine the attitudes toward the use of telephone crisis services (hotlines) among 519 adolescents in 9th through 12th grade mandatory health courses in six high schools in New York State. Few adolescents (2.1%) used hotlines and negative attitudes were stronger toward hotlines than they were toward other formal sources of help. The most common reasons for hotline nonuse related to feelings of self-reliance and shame. Objections to hotlines were strongest among students most in need of help by virtue of impaired functioning or feelings of hopelessness. The results underscore needed outreach efforts to youth.  相似文献   
107.
According to several recent historical accounts, Broca (1865a) stated that left-handers are the mirror-reverse of right-handers for cerebral control of speech, with the right hemisphere being dominant in left-handers, and the left hemisphere dominant in right-handers. The same accounts then note Broca's error in light of current evidence that the majority of left-handers are left-dominant for speech just as are nearly all right-handers. Eling (1984) has called such statements misrepresentations of Broca's position and has argued that Broca's analysis actually was more compatible with the current view that there is a disjunction, meaning an absence of an intimate anatomical relationship, between cerebral control for handedness and speech. The current paper looks again at Broca's work, describes the context in which his views were first articulated, and traces the development of the mirror-reversal principle. The conclusion is reached that, judged by a narrow reading of the 1865 paper, Broca's views could indeed be construed as an anticipation of the modern disjunction principle. However, judged by a broader reading, by consideration of his other writing, and in the context of the philosophical and scientific tradition that shaped his work, it is suggested that it was the mirror-reversal principle to which Broca was actually disposed.  相似文献   
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109.
The purpose of the present research was to examine the influence of cognitive processes on discourse global coherence ability measured across different discourse tasks and collected from younger (n = 40; 20–39 years) and older (n = 40; 70–87 years) cognitively healthy adults. Study participants produced oral language samples in response to five commonly used discourse elicitation tasks and they were analyzed for maintenance of global coherence. Participants also completed memory and attention measures. Group differences on the global coherence scale were found for only one type of discourse—recounts. Across discourse elicitation tasks the lowest global coherence scores were found for recounts compared to the other discourse elicitation tasks. The influence of cognitive processes on maintenance of global coherence differed for the two age groups. For the younger group, there were no observed significant relationships. For the older group, cognitive measures were related to global coherence of stories and procedures.  相似文献   
110.
Since the global financial crisis of 2007/8, proliferating calls for a Keynesian Green New Deal have cast the publicly (and environmentally) minded state as a necessary driver of technological innovation and social transformation, while, vice versa, innovation has moved to political centre-stage. The history and genesis of this particular Green Keynesian paradigm illustrate that some of its most high-profile proponents selectively and problematically frame twentieth-century Keynesianism and the ‘public good’. It is important to examine critically the calls for an ‘entrepreneurial state’ in which Green Keynesian ideas are mobilized in support of an agenda for continued and accelerated development of commercially focused, privately developed green technologies. The entrepreneurial state represents a neoliberal re-appropriation of Green Keynesianism, where dominant financial actors (in Silicon Valley, as opposed to on Wall Street) are tapped as the visionaries who can and should set our collective innovation agenda. Although there is a need for large-scale, coordinated techno-social efforts to address climate change, supporting ‘green’ innovation cannot simply be framed as maximizing ‘innovation’ while taking the ‘state’ for granted. Instead, it must entail a careful assessment of the specific trajectories of innovation being enabled and the underlying socio-natures that they maintain and promote. Science and technology studies (STS)-informed analysis allows, and compels, asking how socio-technological innovation and their constitutive power relations are crucially interrelated, making the reshaping of the state—still the primary institution and system of social relations of collective governance—a core but neglected political, technological and ecological project of our time, with a key role for STS.  相似文献   
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