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541.
Exposure to air pollution is associated with neuroinflammation in healthy children and dogs in Mexico City. Comparative studies were carried out in healthy children and young dogs similarly exposed to ambient pollution in Mexico City. Children from Mexico City (n: 55) and a low polluted city (n:18) underwent psychometric testing and brain magnetic resonance imaging MRI. Seven healthy young dogs with similar exposure to Mexico City air pollution had brain MRI, measurement of mRNA abundance of two inflammatory genes cyclooxygenase-2, and interleukin 1 beta in target brain areas, and histopathological evaluation of brain tissue. Children with no known risk factors for neurological or cognitive disorders residing in a polluted urban environment exhibited significant deficits in a combination of fluid and crystallized cognition tasks. Fifty-six percent of Mexico City children tested showed prefrontal white matter hyperintense lesions and similar lesions were observed in dogs (57%). Exposed dogs had frontal lesions with vascular subcortical pathology associated with neuroinflammation, enlarged Virchow-Robin spaces, gliosis, and ultrafine particulate matter deposition. Based on the MRI findings, the prefrontal cortex was a target anatomical region in Mexico City children and its damage could have contributed to their cognitive dysfunction. The present work presents a groundbreaking, interdisciplinary methodology for addressing relationships between environmental pollution, structural brain alterations by MRI, and cognitive deficits/delays in healthy children.  相似文献   
542.
The focus of this commentary is twofold. First, I examine Faiciuc’s attempts to counter symbolic computationalism as a major theoretical framework for the study of deductive reasoning. Second, I wish to see how far the author goes in her defense of Dynamic Systems Approaches (DSAs) as a more promising framework for explaining logical reasoning. When reading her work, I posed two versions of the same for/against question to myself: How strong is the case against symbolic computationalism? And, on the basis of the author’s argumentation, would one feel justified in adopting DSAs instead? I examine each question in turn, and come to similar conclusions. The article by Faiciuc tackles issues of relevance to any serious effort toward reflecting on the two perspectives being compared. Unfortunately, however, references to studies supporting her claims are rather thin. A better-informed answer to the question raised in the title of the article is still to be given.  相似文献   
543.
Life Tasks and Daily Life Experience   总被引:2,自引:0,他引:2  
ABSTRACT This article explores the assumption that the goals on which an individual works structure the experience of daily life. One set of important goals are those consensual tasks that reflect the age-graded expectations of a living environment (e.g., the task of being on one's own at college). Whereas most members of a common age group share these consensual life tasks, individuals in a group differ in the relative importance they place on different tasks and in their appraisals of them. In the present study of 54 women living in a college sorority, the importance of a life task was associated with increased relevance of the task to daily life events, as revealed in experience sampling. The women were more emotionally involved in events that they saw as highly relevant to their life tasks than in less relevant events and, for each person, positive affect and emotional involvement in task-relevant events were related to her initial life task appraisals.  相似文献   
544.
545.
This is an initial systematic study of the properties of negation from the point of view of abstract deductive systems. A unifying framework of multiple-conclusion consequence relations is adopted so as to allow us to explore symmetry in exposing and matching a great number of positive contextual sub-classical rules involving this logical constant—among others, well-known forms of proof by cases, consequentia mirabilis and reductio ad absurdum. Finer definitions of paraconsistency and the dual paracompleteness can thus be formulated, allowing for pseudo-scotus and ex contradictione to be differentiated and for a comprehensive version of the Principle of Non-Triviality to be presented. A final proposal is made to the effect that—pure positive rules involving negation being often fallible—a characterization of what most negations in the literature have in common should rather involve, in fact, a reduced set of negative rules.  相似文献   
546.
Over recent years, various semantics have been proposed for dealing with updates in the setting of logic programs. The availability of different semantics naturally raises the question of which are most adequate to model updates. A systematic approach to face this question is to identify general principles against which such semantics could be evaluated. In this paper we motivate and introduce a new such principle the refined extension principle. Such principle is complied with by the stable model semantics for (single) logic programs. It turns out that none of the existing semantics for logic program updates, even though generalisations of the stable model semantics, comply with this principle. For this reason, we define a refinement of the dynamic stable model semantics for Dynamic Logic Programs that complies with the principle.  相似文献   
547.
Confessions, the narrative of Augustine’s spiritual journey, has been a source of inspiration to readers through many centuries. It addresses the universal striving of the individual towards a ‘way of living’ characterized by internal coherence and an experience of the transcendent. Augustine, using a method of inquiry and engagement, guides the reader through some fundamental exercises: remembering one’s story; facing inner restlessness; entering into dialogue with God; ordering of human love; centering in Christ; participating in a community of faith; living as a pilgrim. Together, they constitute a didactic instrument for the spiritual development of his readers. This paper reconstructs that central purpose in a coherent and practical model.  相似文献   
548.
There is general consensus that performance on a number of cognitive tasks deteriorates following total sleep deprivation. At times, however, subjects manage to maintain performance. This may be because of an ability to switch cognitive strategies including the exertion of compensatory effort. The present study examines the effects of total sleep deprivation on a semantic word priming task. Word priming is unique because it can be carried out using different strategies involving either automatic, effortless or controlled, effortful processing. Twelve subjects were presented with word pairs, a prime and a target, that were either highly semantically associated (cat…dog), weakly associated (cow…barn) or unassociated (apple…road). In order to increase the probability of the use of controlled processing following normal sleep, the subject’s task was to determine if the target word was semantically related to the prime. Furthermore, the time between the offset of the prime and the onset of the target was relatively long, permitting the use of an effortful, expectancy-predictive strategy. Event-related potentials (ERPs) were recorded from 64 electrode sites. After normal sleep, RTs were faster and accuracy higher to highly associated targets; this performance advantage was also maintained following sleep deprivation. A large negative deflection, the N400, was larger to weakly associated and unassociated targets in both sleep-deprived and normal conditions. The overall N400 was however larger in the normal sleep condition. Moreover, a long-lasting negative slow wave developed between the offset of the prime and the onset of the target. These physiological measures are consistent with the use of an effortful, predictive strategy following normal sleep but an automatic, effortless strategy following total sleep deprivation. A picture priming task was also run. This task benefits less from the use of a predictive strategy. Accordingly, in this task, ERPs following the target did not differ as a function of the amount of sleep.  相似文献   
549.
The present study is designed to test the role of immersion and media content in the sense of presence. Specifically, we are interested in the affective valence of the virtual environments. This paper describes an experiment that compares three immersive systems (a PC monitor, a rear projected video wall, and a head-mounted display) and two virtual environments, one involving emotional content and the other not. The purpose of the experiment was to test the interactive role of these two media characteristics (form and content). Scores on two self-report presence measurements were compared among six groups of 10 people each. The results suggest that both immersion and affective content have an impact on presence. However, immersion was more relevant for non-emotional environments than for emotional ones.  相似文献   
550.
While inattentional blindness is a modern classic in attention and perception research, analogous phenomena of inattentional deafness have been widely neglected. We here present the first investigation of inattentional deafness in and with music under controlled experimental conditions. Inattentional deafness in music is defined as the inability to consciously perceive an unexpected musical stimulus when attention is focused on a certain facet of the piece. Participants listened to a modification of the first 1′50″ of Richard Strauss’ Thus Spake Zarathustra; while the control group just listened, the experimental group had to count the number of timpani beats. An e-guitar solo served as the unexpected event. In Study 1, experimental data from n = 115 participants were analyzed. Non-musicians were compared with musicians to investigate the impact of expertise. In Study 2 (n = 47), the scope of the inattentional deafness effect was investigated with a more salient unexpected stimulus. Results demonstrate an inattentional deafness effect under dynamic musical conditions. Quite unexpectedly, the effect was structurally equivalent even for musicians. Our findings clearly show that sustained inattentional deafness exists in the musical realm, in close correspondence to inattentional blindness with dynamic visual stimuli.  相似文献   
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