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111.
For first order languages with no individual constants, empty structures and truth values (for sentences) in them are defined. The first order theories of the empty structures and of all structures (the empty ones included) are axiomatized with modus ponens as the only rule of inference. Compactness is proved and decidability is discussed. Furthermore, some well known theorems of model theory are reconsidered under this new situation. Finally, a word is said on other approaches to the whole problem.  相似文献   
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The conception and the determination of brain death continue to raise scientific, legal, philosophical, and religious controversies. While both the President’s Commission for the Study of Ethical Problems in Medicine and Biomedical and Behavioral Research in 1981 and the President’s Council on Bioethics in 2008 committed to a biological definition of death as the basis for the whole-brain death criteria, contemporary neuroscientific findings augment the concerns about the validity of this biological definition. Neuroscientific evidentiary findings, however, have not yet permeated discussions about brain death. These findings have critical relevance (scientifically, medically, legally, morally, and religiously) because they indicate that some core assumptions about brain death are demonstrably incorrect, while others lack sufficient evidential support. If behavioral unresponsiveness does not equate to unconsciousness, then the philosophical underpinning of the definition based on loss of capacity for consciousness as well as the criteria, and tests in brain death determination are incongruent with empirical evidence. Thus, the primary claim that brain death equates to biological death has then been de facto falsified. This conclusion has profound philosophical, religious, and legal implications that should compel respective authorities to (1) reassess the philosophical rationale for the definition of death, (2) initiate a critical reappraisal of the presumed alignment of brain death with the theological definition of death in Abrahamic faith traditions, and (3) enact new legislation ratifying religious exemption to death determination by neurologic criteria.  相似文献   
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This paper highlights a symposium on stress risk factors and stress susceptibility, presented at the Neurobiology of Stress workshop in Boulder, CO, in June 2010. This symposium addressed factors linking stress plasticity and reactivity to stress pathology in animal models and in humans. Dr. J. Radley discussed studies demonstrating prefrontal cortical neuroplasticity and prefrontal control of hypothalamo-pituitary-adrenocortical axis function in rats, highlighting the emerging evidence of the critical role that this region plays in normal and pathological stress integration. Dr. M. Kabbaj summarized his studies of possible epigenetic mechanisms underlying behavioral differences in rat populations bred for differential stress reactivity. Dr. L. Jacobson described studies using a mouse model to explore the diverse actions of antidepressants in brain, suggesting mechanisms whereby antidepressants may be differentially effective in treating specific depression endophenotypes. Dr. R. Yehuda discussed the role of glucocorticoids in post-traumatic stress disorder (PTSD), indicating that low cortisol level may be a trait that predisposes the individual to development of the disorder. Furthermore, she presented evidence indicating that traumatic events can have transgenerational impact on cortisol reactivity and development of PTSD symptoms. Together, the symposium highlighted emerging themes regarding the role of brain reorganization, individual differences, and epigenetics in determining stress plasticity and pathology.  相似文献   
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The perception of speech and music requires processing of variations in spectra and amplitude over different time intervals. Near-term fetuses can discriminate acoustic features, such as frequencies and spectra, but whether they can process complex auditory streams, such as speech sequences and more specifically their temporal variations, fast or relatively slow acoustic variations, is unclear. We recorded the cardiac activity of 82 near-term fetuses (38 weeks GA) in quiet sleep during a silent control condition and four 15 s streams presented at 90 dB SPL Leq: two piano melodies with opposite contours, a natural Icelandic sentence and a chimera of the sentence--all its spectral information was replaced with broadband noise, leaving its specific temporal variations in amplitude intact without any phonological information. All stimuli elicited a heart rate deceleration. The response patterns to the melodies were the same and differed significantly from those observed with the Icelandic sentence and its chimera, which did not differ. The melodies elicited a monophasic heart rate deceleration, indicating a stimulus orienting reflex while the Icelandic and its chimera evoked a sustained lower magnitude response, indicating a sustained attentional response or more focused information processing. A conservative interpretation of the data is that near-term fetuses can perceive sound streams and the rapid temporal variations in amplitude that are specific to speech sounds with no spectral variations at all.  相似文献   
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The executive functions of inhibition and shifting were studied in arithmetic-disabled children, reading-disabled children, reading plus arithmetic-disabled children, and controls (N = 74). Measures involved the rapid naming of objects, digits, letters, or quantities with or without additional task requirements that reflected inhibition or shifting. Also, the Making Trails task, reflecting shifting, was administered. For tasks without executive demands, arithmetic-disabled children were slower in the naming of digits and quantities, whereas reading-disabled children were slower in the naming of digits and letters. For the executive tasks, arithmetic-disabled children as well as reading plus arithmetic-disabled children were impaired on the Making Trails task and on an object naming task that required both inhibition and shifting. Reading-disabled children exhibited no problems in executive functioning. Furthermore, it was shown that reading plus arithmetic-disabled children experienced the combination of problems that characterize children with a single learning deficit.  相似文献   
118.
Construct validity is the hallmark of Templer's Death Anxiety Scale (1970), which has generated a healthy stream of research of paramount importance in the USA and all over the world. This paper contends that scores on this scale provide valuable scientific knowledge on group norms. To expand the concept of death anxiety it is necessary to supplement empirical with qualitative research. Persons with the same scores may show qualitatively different fears of death, and vice versa. Total reliance on empirical scales may not disclose the depth of bipolar meaning in a "life-death anxiety." Templer's scale is a mixture of fears, phobias, and obsessions with thoughts of illness, cancer, heart disease, and wars. A bipolar "life-death anxiety" continuum requires phenomenology to reach beyond the 15 items to the process of "experiencing." The scale addresses "thoughts" about the death of others even though its items are cast in the first person singular. This provides group norms of a "cognitive-affective" construct, with limited generality cross-culturally. Means do not disclose fully meaningful comparisons between persons or cultures. Death Anxiety as an existential anticipatory mode of "being-in-the-world" is embedded in a personal/genetic/cultural matrix that may vary individually and culturally.  相似文献   
119.
A total of 107 Malay primary school girls (8-9 yr. old) completed a set of measurements on eating behavior (ChEAT, food neophobia scales, and dieting experience), the Rosenberg Self-Esteem Scale, body shape satisfaction, dietary intake, weight, and height. About 38% of the girls scored 20 and more on the ChEAT, and 46% of them reported dieting by reducing sugar and sweets (73%), skipping meals (67%), reducing fat foods (60%) and snacks (53%) as the most frequent methods practiced. In general, those girls with higher ChEAT scores tended to have lower self-esteem (r=.39), indicating they were more unwilling to try new foods (food neophobic) (r=.29), chose a smaller figure for desired body size (r=-.25), and were more dissatisfied with their body size (r=.31).  相似文献   
120.
Recent data indicate that the familiarity and the emotional expression of faces occur at an early stage of information processing. The goal of the present study was to determine whether these two aspects interact at the structural encoding stage as reflected by the N170 component of event-related potentials in tasks requiring the subjects either to identify whether the faces were familiar or the nature of the emotional expression. The results indicate that the neural responses to level of familiarity and emotional expression were observable at this early processing stage but without interacting. In particular, faces of personal importance to the subjects differed from those of less personal importance. Because familiarity did not interact with emotional expression at behavioral and electrophysiologic levels, our results support the contention of parallel and independent processing of faces.  相似文献   
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