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In Computer Science stepwise refinement of algebraic specifications is a well-known formal methodology for rigorous program development. This paper illustrates how techniques from Algebraic Logic, in particular that of interpretation, understood as a multifunction that preserves and reflects logical consequence, capture a number of relevant transformations in the context of software design, reuse, and adaptation, difficult to deal with in classical approaches. Examples include data encapsulation and the decomposition of operations into atomic transactions. But if interpretations open such a new research avenue in program refinement, (conceptual) tools are needed to reason about them. In this line, the paper’s main contribution is a study of the correspondence between logical interpretations and morphisms of a particular kind of coalgebras. This opens way to the use of coalgebraic constructions, such as simulation and bisimulation, in the study of interpretations between (abstract) logics.  相似文献   
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Proof-theoretic semantics is an inferentialist theory of meaning, usually developed in a multiple-assumption and single-conclusion framework. In that framework, this theory seems unable to justify classical logic, so some authors have proposed a multiple-conclusion reformulation to accomplish this goal. In the first part of this paper, the debate originated by this proposal is briefly exposed and used to defend the diverging opinion that proof-theoretic semantics should always endorse a single-assumption and single-conclusion framework. In order to adopt this approach some of its criteria of validity, especially separability, need to be weakened. This choice is evaluated and defended. The main argument in this direction is based on the circular dependences of meaning between multiple assumptions and conjunctions, and between multiple conclusions and disjunctions. In the second part of this paper, some systems that suit the new requirements are proposed for both intuitionistic and classical logic. A proof that they are valid, according to the weakened criteria, is sketched.

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The aim of this study was to compare the speed fluctuation and the drag force in young swimmers between genders. Twenty-three young pubertal swimmers (12 boys and 11 girls) volunteered as subjects. Speed fluctuation was measured using a kinematical mechanical method (i.e., speedo-meter) during a maximal 25-m front crawl bout. Active drag, active drag coefficient and power needed to overcome drag were measured with the velocity perturbation method for another two maximal 25 m front crawl bouts with and without the perturbation device. Passive drag and the passive drag coefficient were estimated using the gliding decay velocity method after a maximal push-off from the wall while being fully immersed. The technique drag index was also assessed as a ratio between active and passive drag. Boys presented meaningfully higher speed fluctuation, active drag, power needed to overcome drag and technique drag index than the girls. There were no significant gender differences for active drag coefficient, passive drag and passive drag coefficient. There were positive and moderate-strong associations between active drag and speed fluctuation when controlling the effects of swim velocity. So, increasing speed fluctuation leads to higher drag force values and those are even higher for boys than for girls.  相似文献   
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Structural synaptic changes occur in medial prefrontal cortex circuits during remote memory formation. Whether extinction reverts or further reshapes these circuits is, however, unknown. Here we show that the number and the size of spines were enhanced in anterior cingulate (aCC) and infralimbic (ILC) cortices 36 d following contextual fear conditioning. Upon extinction, aCC spine density returned to baseline, but the enhanced proportion of large spines did not. Differently, ILC spine density remained elevated, but the size of spines decreased dramatically. Thus, extinction partially erases the remote memory network, suggesting that the preserved network properties might sustain reactivation of extinguished conditioned fear.  相似文献   
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Older adults are not as good as younger adults at decoding prosodic emotions. We sought to determine the specificity of this finding. Performance of older and younger adults was compared on a prosodic emotion task, a "pure" prosodic emotion task, a linguistic prosody task, and a "pure" linguistic prosody task. Older adults were less accurate at interpreting prosodic emotion cues and nonemotional contours, concurrent semantic processing worsened interpretation, and performance was further degraded when identifying negative emotions and questions. Older adults display a pervasive problem interpreting prosodic cues, but further study is required to clarify the stage at which performance declines.  相似文献   
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Alexithymia has been described as an important dimension in several medical and psychiatric diseases. Chronic urticaria (CU) is a chronic condition, in which treatment is difficult. Our aim is to determine the prevalence of alexithymia traits in patients with CU, and to identify the relationships between alexithymia and psychological variables and quality-of-life dimensions. Fifty-five sequential CU patients in a faculty ambulatory specialized consultation, with an average age of 44.92, were compared with 31 healthy volunteers. Both groups were studied by means of validated scales for alexithymia (Toronto Alexithymia Scale [TAS-20]), attachment (Adult Attachment Scale-R [AAS-R]), psychopathology (Brief Symptom Inventory [BSI]), personality dimensions (The NEO Five-Factor inventory [NEO-FFI]) and quality of life (Short Form-36 [SF-36]). The classification of CU reactions was obtained from the patient's history, physical examination, laboratory assessment and histopathologic findings. All the patients were under treatment with sedating H1-antihistamines, non-sedating H1-antihistamines combination of H1 and H2 blocker, 2 H1-antihistamines and 3 H1-antihistamines. High traits of alexithymia were found on CU patients (56.9%) as well as high symptom rates of anxiety. Alexithymia traits were significantly positively correlated with insecure attachment styles, with psychopathological symptoms, and with the defense mechanism turn against self. We also reported a significant negative correlation between alexithymia traits and the dimensions of quality of life. Insecure attachment styles were positively correlated with psychopathological symptoms and negatively correlated with quality of life. We did not find significant statistical correlations between alexithymia and clinical variables. CU patients present serious difficulty in dealing with emotion arousal. There is strong evidence of a psychosomatic specificity in CU, with marked alexithymic traits.  相似文献   
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Theories about conceptual change have been generally related to historical and philosophical analysis of science. Yet, there is still much debate on how ideas coming from the history of science and their implications can be applied in this field. Our study intends to investigate the complex structure of conceptual change, by making use of some particularly representative features of the History and Philosophy of science, while considering the structure of so-called crucial experiments and the specific role of implicit hypotheses. Due to their historical importance and logical reasoning aspects, examining these issues may contribute to understand how conceptual change may take place.  相似文献   
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