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131.
A series of three experiments examined children's sensitivity to probabilistic phonotactic structure as reflected in the relative frequencies with which speech sounds occur and co-occur in American English. Children, ages 212 and 312 years, participated in a nonword repetition task that examined their sensitivity to the frequency of individual phonetic segments and to the frequency of combinations of segments. After partialling out ease of articulation and lexical variables, both groups of children repeated higher phonotactic frequency nonwords more accurately than they did low phonotactic frequency nonwords, suggesting sensitivity to phoneme frequency. In addition, sensitivity to individual phonetic segments increased with age. Finally, older children, but not younger children, were sensitive to the frequency of larger (diphone) units. These results suggest not only that young children are sensitive to fine-grained acoustic-phonetic information in the developing lexicon but also that sensitivity to all aspects of the sound structure increases over development. Implications for the acoustic nature of both developing and mature lexical representations are discussed. 相似文献
132.
Free Łukasiewicz and Hoop Residuation Algebras 总被引:2,自引:1,他引:1
Hoop residuation algebras are the {, 1}-subreducts of hoops; they include Hilbert algebras and the {, 1}-reducts of MV-algebras (also known as Wajsberg algebras). The paper investigates the structure and cardinality of finitely generated free algebras in varieties of k-potent hoop residuation algebras. The assumption of k-potency guarantees local finiteness of the varieties considered. It is shown that the free algebra on n generators in any of these varieties can be represented as a union of n subalgebras, each of which is a copy of the {, 1}-reduct of the same finite MV-algebra, i.e., of the same finite product of linearly ordered (simple) algebras. The cardinality of the product can be determined in principle, and an inclusion-exclusion type argument yields the cardinality of the free algebra. The methods are illustrated by applying them to various cases, both known (varieties generated by a finite linearly ordered Hilbert algebra) and new (residuation reducts of MV-algebras and of hoops). 相似文献
133.
Four-month-olds' memory for surface feature and location information was tested following brief occlusions. When the target objects were images of female faces or monochromatic asterisks infants showed increased looking times following a change in identity or color but not following a change in location or combinations of feature and location information. When the target objects were images of manipulable toys, the infants showed increased looking times following a change in location but not identity or the binding of location and identity information. This evidence is consistent with the idea that young infants are unable to maintain the information processed separately in both the dorsal and ventral visual streams during occlusions. Our results suggest that it is the target's affordance for action that determines whether the dorsal or ventral information is selectively maintained during occlusion. 相似文献
134.
The paper discusses the similarity between geometry, arithmetic, and logic, specifically with respect to the question of whether applied theories of each may be revised. It argues that they can - even when the revised logic is a paraconsistent one, or the revised arithmetic is an inconsistent one. Indeed, in the case of logic, it argues that logic is not only revisable, but, during its history, it has been revised. The paper also discusses Quine's well known argument against the possibility of logical deviancy. 相似文献
135.
136.
David K. Carson Kent W. Becker Kevin E. Vance Nancy L. Forth 《Contemporary Family Therapy》2003,25(1):89-109
The purpose of this study, using an online methodology, was to investigate therapists' perceptions of the role of creativity in couples' and family therapy. Along with completing a quantitative measure assessing creativity in their work, participants responded to four open-ended questions which addressed the meaning of creativity, characteristics of a creative family therapist, some creative interventions they have used with couples and families, and barriers to their own creativity as a family therapist. A total of 142 marriage and family therapists in 36 states in the United States participated. The findings shed light on the unique importance of creativity in couples and family treatment. 相似文献
137.
Using the work of Józef Bocheski as apositive example, this paper sets out the casefor a balanced use of historical knowledge indoing analytic philosophy. Between the twoextremes of relativizing historicism, whichdenies absolute truth, and arrogant scientism,which denies any constructive role for thehistory of ideas in philosophy, lies a viamedia in which historical reflection onconcepts and their history is placed at theservice of the system of cognitive philosophy.Knowledge of the history of philosophy, whilenot a sine qua non, can empower analyticphilosophy to push forward to new and moresatisfactory solutions to old and new problems.Examples are adduced from Bocheski's oeuvreand from the author's own experience. 相似文献
138.
Riolobos AS Heredia M de la Fuente JA Criado JM Yajeya J Campos J Santacana M 《Neurobiology of learning and memory》2001,75(3):274-292
The long-term effect of transplanting embryonic frontal cortex into a unilateral frontal cortex lesion has been studied in adult rats. Before surgery, activity in an open field, muscular strength of both forelimbs, and performance in a paw-reaching-for-food task were scored in 26 rats. In 21 animals a unilateral cortex lesion was then made in the forelimb motor area of the hemisphere contralateral to the preferred paw in the paw-reaching-for-food task, while the other 5 animals were sham-operated. On retesting, the lesion animals changed the preferred paw. A solid homotopic transplant of embryonic tissue (embryonic day 17) was then placed in the lesion cavity in 11 of the lesion rats. Three months later neither lesion alone nor lesion plus transplantation affected open field behavior and muscular strength, but the lesion permanently affected performance in the paw-reaching-for-food task, as shown by a change of preferred paw and a functional deficit in the paw contralateral to the lesion. Transplantation ameliorated the deficits caused by the lesion, but this was only evident when animals were forced to reach with the paw contralateral to the lesion plus transplant. The behavioral results were independent of the size of the lesion and graft. Connections between graft and host tissue were studied by means of the fluorescent tracer 1,1'-dioctadecyl-3,3,3'3'-tetramethylindocarbocyanine perchlorate (DiI). A dense array of labeled fibers was found in the host cortex adjacent to the transplant. The results suggest that functional recovery depends on grafting but is only evident when the animal is obliged to use the affected limb. 相似文献
139.
This article reports on the development and teaching of compulsory courses on ethics and engineering at Delft University of
Technology (DUT). Attention is paid to the teaching goals, the educational setup and methods, the contents of the courses,
involvement of staff from engineering schools, experiences to date, and challenges for the future. The choices made with respect
to the development and teaching of the courses are placed within the European and Dutch context and are compared and contrasted
with the American situation and experiences.
Previous versions of this article were presented at the meeting of the SEFI Working Group on Engineering Ethics in Rzeszow,
Poland, April 29–May 1, 1999 and at the SEFI Annual Conference in Zurich, Switzerland, September 1–3, 1999. 相似文献
140.
It was tested whether boys with attention-deficit/hyperactivity disorder (ADHD), subgrouped by aggressive status, would show higher rates of depressive symptomatology and lower levels of self-esteem than would comparison boys and, in a subsample, explored attributional mechanisms that may be related to such internalizing features. Study 1 utilized 114 boys with ADHD (all prior recipients of stimulant medication) and 87 comparison boys, aged 7–12 years. Aggressive boys with ADHD reported more symptoms of depression than did nonaggressive boys with ADHD, who, in turn, reported more depression than did comparison boys. Effect sizes were moderate to large and did not vary with a depression rating scale uncontaminated by ADHD-related items. For self-esteem, the most pronounced effect was that aggressive boys with ADHD showed lower levels than did nonaggressive ADHD or comparison boys; effects were again moderate to large. Study 2 participants were a subsample of boys with ADHD from Study 1 (N = 27). We probed causal attributions in ADHD-related domains through responses to hypothetical vignettes, in which the protagonist's medication status (medicated, not medicated) was crossed with type of outcome (good, bad). Medication-related attributions were frequent. In describing the protagonist's success in relation to medication treatment, the sample showed significant associations between (a) medication-related attributions and (b) increased depressive symptomatology as well as decreased self-esteem. We discuss attributional processes that may help to explain the variation in internalizing symptoms among children with ADHD. 相似文献