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51.
The Priestley duality for Wajsberg algebras   总被引:1,自引:1,他引:0  
The Priestley duality for Wajsberg algebras is developed. The Wajsberg space is a De Morgan space endowed with a family of functions that are obtained in rather natural way.As a first application of this duality, a theorem about unicity of the structure is given.  相似文献   
52.
The essay examines the argument advanced by E.D. Hirsch, Jr., for instituting ‘cultural literacy’ as a fundamental priority of schools. A number of confusions and equivocations in Hirsch's reasoning are identified, and the propensity of his project to indoctrinate is exposed. Among the features of Hirsch's argument shown to be troubling are his shifting construal of ‘language’, his inconsistency about the requirements of cultural literacy, and his uncritical relation to traditional images of the American past and present. The upshot is to raise the question why Hirsch's project has elicited wide support and praise.  相似文献   
53.
Tested a 7-month, media-based, community intervention among Hispanics in San Francisco designed to change levels of information on the damaging effects of cigarette smoking and on the availability of culturally appropriate cessation services. Three community-wide surveys of Hispanics were conducted with independent random samples, two as baselines (n = 1,660 and 2,053) and one postintervention (n = 1,965). Results showed that changes in the level of awareness of cessation services had taken place after implementation of the intervention. Furthermore, those changes took place primarily among the less acculturated Spanish-speaking Hispanics who were the target of the intervention. The changes in information reported here demonstrate that a culturally appropriate information dissemination campaign that utilizes multiple channels can produce changes in a community's level of information even when the campaign is implemented for a relatively short period.  相似文献   
54.
Earlier research has shown that extraverts tend to increase their visual evoked potential amplitudes with increasing light intensity (augmenting), while introverts reach their maximum amplitude at lower intensities (reducing). The evoked response has normally been measured from association areas of the brain (at the vertex). The present study measured VEP amplitudes over visual cortex and at the vertex, using four light intensities in two conditions, where attention was either directed towards the light stimuli, or away from them by a concurrent auditory task. Forty subjects were classified as extraverts or introverts based on the Eysenck Personality Inventory. The results show that attention interacted significantly with extraversion. Introverts exhibited a narrower focus of attention, while higher amplitudes and amplitude-intensity functions when attending to the light flashes and lower when distracted. Extraverts showed smaller differences between conditions, indicating a more evenly distributed attention. Higher arousal in introverts is the probable cause of their narrower focus of attention. There were marked differences in the distribution of activity between vertex and occipital cortex. Introverts showed relatively stronger occipital responses and extraverts stronger vertex responses across all intensities and in both conditions. The predisposition for mainly perceptual responses to aversive stimuli in introverts, and for general alerting and motor preparatory responses in extraverts, are interpreted as supportive of Brebner and Cooper's hypothesis that introverts are ‘geared to inspect’ and extraverts are ‘geared to respond’.  相似文献   
55.
The relational communication of sixteen dropout versus sixteen continuation sessions of solution-focused therapy was studied using two different coding schemes. On the Topic Initiation/Topic Following coding scheme (Tracey, 1986) no differences were found between dropout and continuation sessions, whereas the Family-Relational Communication Control Coding Scheme (Heatherington and Friedlander, 1987) yielded a number of significant findings. Both in 'successful' and in 'unsuccessful' dropout sessions, therapeutic interaction was found to be more conflictive than in continuation cases, with clients showing more domineering behaviour in dropout than in continuation sessions. Markovian and lag sequential analysis are used to clarify some of these findings, and their implications are discussed.  相似文献   
56.
In this review, we consider three possible criteria by which knowledge might be regarded as implicit or inaccessible: It might be implicit only in the sense that it is difficult to articulate freely, or it might be implicit according to either an objective threshold or a subjective threshold. We evaluate evidence for these criteria in relation to artificial grammar learning, the control of complex systems, and sequence learning, respectively. We argue that the convincing evidence is not yet in, but construing the implicit nature of implicit learning in terms of a subjective threshold is most likely to prove fruitful for future research. Furthermore, the subjective threshold criterion may demarcate qualitatively different types of knowledge. We argue that (1) implicit, rather than explicit, knowledge is often relatively inflexible in transfer to different domains, (2) implicit, rather than explicit, learning occurs when attention is focused on specific items and not underlying rules, and (3) implicit learning and the resulting knowledge are often relatively robust.  相似文献   
57.
Subjects were presented with briefly exposed visual displays of words that were common first names with a length of four to six letters. In the main experiment, each display consisted of four words: two names shown in red and two shown in white. The subject’s task was to report the red names (targets), but ignore the white ones (distractors). On some trials the subject’s own name appeared as a display item (target or distractor). Presentation of the subject’s name as a distractor caused no more interference with report of targets than did presentation of other names as distractors. Apparently, visual attention was not automatically attracted by the subject’s own name.  相似文献   
58.
Tested a theoretical model on the effects of social role identity, illness intrusion, and competence on psychological well-being among 109 low-income Latinas with arthritis. All six roles studied were rated as highly important identities. Sex-role nontraditionalism was associated with less importance of the homemaker, mother, and grandmother roles. Negative affect increased as a function of intrusions into valued identities. Having important role identities contributed to feelings of competence (i.e., self-esteem and self-efficacy), which in turn, contributed to psychological well-being. Competence also mediated the effects of pain, identity, and illness intrusions on psychological well-being. Results suggest competence processes play an important role in well-being.  相似文献   
59.
For over 20 years the medical literature has carefully documented the undertreatment of all types of pain by physicians. During this same period, as the field of bioethics came of age, the phenomenon of undertreated pain received almost no attention from the bioethics literature. This article takes bioethicists to task for failing to recognize the undertreatment of pain as a major ethical, and not merely a clinical, failing of the medical profession. The nature and extent of the problem of undertreated pain is examined, as well as possible reasons for its disregard by bioethicists. The factors contributing to undertreated pain in the clinical setting are considered, as well as the hazards posed by recent failures to address ethically questionable clinical practices. Finally, suggestions are offered for refocusing the attention of bioethicists to this significant problem.  相似文献   
60.
The etiology of the observed relationship between general cognitive ability and reading performance was investigated by analyzing data from samples of twin pairs tested in the Colorado Learning Disabilities Research Center. Bivariate phenotypic and genetic structural equation models were fitted to data from 486 twin pairs selected for reading deficits (276 identical and 210 same-sex fraternal) and 314 control pairs (195 identical and 119 same-sex fraternal). Subtests of the Peabody Individual Achievement test (Reading Recognition, Reading Comprehension, and Spelling) were used as measures of reading performance, and verbal and performance IQ scores from the Wechsler Intelligence Scale for Children-Revised (WISC-R) or Wechsler Adult Intelligence Scale-Revised (WAIS-R) were used as indices of general cognitive ability. The results of these confirmatory factor analyses indicate that shared environmental influences do not contribute significantly to covariation between general cognitive ability and reading performance. In contrast, genetic influences contribute substantially to the relationship between the two latent factors. Moreover, the genetic and phenotypic variances of reading performance in the proband group are larger than those in controls, whereas both the genetic and phenotypic correlations between reading performance and general cognitive ability are lower in probands. These results are consistent with recent reports that reading disability may be caused by one or more genes with major effects.  相似文献   
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