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The notion of unsharp orthoalgebra is introduced and it is proved that the category of unsharp orthoalgebras is isomorphic to the category of D-posets. A completeness theorem for some partial logics based on unsharp orthoalgebras, orthoalgebras and orthomodular posets is proved.  相似文献   
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The present paper deals with the predicate version MTL of the logic MTL by Esteva and Godo. We introduce a Kripke semantics for it, along the lines of Ono's Kripke semantics for the predicate version of FLew (cf. [O85]), and we prove a completeness theorem. Then we prove that every predicate logic between MTL and classical predicate logic is undecidable. Finally, we prove that MTL is complete with respect to the standard semantics, i.e., with respect to Kripke frames on the real interval [0,1], or equivalently, with respect to MTL-algebras whose lattice reduct is [0,1] with the usual order.  相似文献   
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Abstract

We tested if ACL-reconstructed participants show a decreased quadriceps torque, a lower muscle endurance capacity and a higher peak torque variability compared to unimpaired control participants prior to and following local muscle fatigue. Participants (n?=?19, 10 women; 25?±?5yrs.) with unilateral hamstrings autograft ACL-reconstruction and a matched unimpaired control group were recruited. Participants performed two maximal isometric voluntary force (MIVF) contractions of the knee extensors. In between, standardized local muscle fatigue was induced. ACL-reconstructed knees display a lower peak torque of the knee extensors in comparison to the contralateral limb (3.2?±?.3Nm/kg vs. 3.5?±?.3 Nm/kg). Peak torque variability and fatigue resistance were not affected by local muscle fatigue (p > .05). Participants with ACL-reconstructed knees show a persistent quadriceps muscle dysfunction. This dysfunction and lower limb side asymmetries might be risk factors for ACL re-ruptures.  相似文献   
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The effects of differing levels of word knowledge on infants’ sequential touching behaviors were investigated in two studies. In both, parent report was used to assess three levels of word knowledge: known, frontier, and unknown. In the first study, 14-month-old infants sequentially touched objects consistent with parents’ reports of their word knowledge. In the second study, 20-month-old infants sequentially touched objects by both conceptual category and reported level of word knowledge. It appears that even infants, like adults, can make distinctions among objects on the basis of their knowledge about the objects’ labels.  相似文献   
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认知方式与幼儿部分遮挡绘画关系的研究   总被引:2,自引:1,他引:2  
本研究考察了5—6岁儿童不同认知方式对部分遮挡绘画任务的影响。实验设定不同形式的误导情境,共有两部分组成。研究结果表明:1.儿童绘画表征水平的发展存在个别差异。2.在误导情境下,场独立儿童比场依存儿童能保持较稳定的策略选择倾向。3.画两个相同物体的遮挡要难于画两个不同物体的遮挡。4.在符号概念编码和空间编码中间存在着一些过渡形态。  相似文献   
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In this article we identify three previously unnoticed problems with flexible moral theories, i.e., theories according to which different moral rules apply when there is full compliance and when there is partial compliance. The first problem is that flexible theories are necessarily very complex, which undermines their ability to motivate and guide action. The second problem is that flexible theories allow for a troubling kind of (moral) domination: the duties an agent has depend on other agents' willingness to comply. Finally, flexible theories introduce indeterminacy: it is sometimes impossible to determine which moral rules apply. When agents stand at the threshold—i.e., when a different rule would apply if a single additional act of noncompliance took place—it is impossible to determine which rule should apply.  相似文献   
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ObjectivesConscious engagement in movement control can influence motor performance. In most cases, the left hemisphere of the brain plays an important role in verbal-analytical processing and reasoning, so changes in the balance of hemispheric activation may influence conscious engagement in movement. Evidence suggests that unilateral hand contractions influence hemispheric activation, but no study has investigated whether there is an associated effect of hand contractions on verbal-analytical processing during motor performance. This study utilized psychophysiological (and behavioural) measures to examine whether pre-performance unilateral hand contraction protocols change verbal-analytical engagement during motor performance.DesignA repeated measures crossover design was employed.MethodsTwenty-eight participants completed three hand contraction protocols in a randomised order: left-, right- and no-hand contractions. Electroencephalography (EEG) measures of hemispheric asymmetry were computed during hand contractions. A golf putting task was conducted after each protocol. EEG connectivity between sites overlying the left verbal-analytical temporal region (T7) and the motor planning region (Fz) was computed for the 3 sec prior to movement initiation. Additionally, electrocardiography (ECG) and electromyography (EMG) signals were analysed 6 sec prior to movement initiation until 6 sec after. Golf putting performance (distance from the target) and putter swing kinematics were measured.ResultsContralateral hemisphere activity was revealed for the left-hand and right-hand contraction conditions. During motor planning, the left-hand contraction protocol led to significantly lower T7-Fz connectivity, and the right-hand contraction protocol led to significantly higher T7-Fz connectivity than the other conditions. EMG, ECG and kinematic measures did not differ as a function of condition. Importantly, T7-Fz connectivity mediated the relationship between hand squeezing and motor performance (distance from the target).ConclusionThe EEG results suggest that pre-performance unilateral hand contractions influence the extent of verbal-analytical engagement during motor planning, which in turn influences motor performance. However, the hand contractions did not influence cardiac activity, muscle activity or kinematics.  相似文献   
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Most people strive toward establishing long-term romantic relationships, and the majority eventually succeed in doing so, which raises the question of how people meet prospective mates. In the current research, we used in-depth interviews and open-ended questionnaires in a sample of 218 Greek-speaking participants, and we identified 44 acts that people perform in order to meet prospective mates, and 17 categories indicating where people met their current or previous mates. In addition, we used quantitative research methods in a sample of 821 Greek-speaking participants, and we classified these acts into eight broader strategies. The most frequently adopted ones, included demonstrating active interest to prospective mates, going out to bars, clubs and cafés, improving one's looks and asking friends to introduce one to available individuals. For several strategies, we found significant sex and age effects. Furthermore, most participants indicated that they met their current and previous partners from friends and acquaintances, in school or university, on social media, and on a night out.  相似文献   
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