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We use a deontic logic of collective agency to study reducibility questions about collective agency and collective obligations. The logic that is at the basis of our study is a multi-modal logic in the tradition of stit (‘sees to it that’) logics of agency. Our full formal language has constants for collective and individual deontic admissibility, modalities for collective and individual agency, and modalities for collective and individual obligations. We classify its twenty-seven sublanguages in terms of their expressive power. This classification enables us to investigate reducibility relations between collective deontic admissibility, collective agency, and collective obligations, on the one hand, and individual deontic admissibility, individual agency, and individual obligations, on the other.
相似文献Assessments for spatial working memory (SWM) in pet dogs that can detect age-related cognitive deficits in a single session may aid in diagnosing canine dementia and may facilitate translational research on Alzheimer’s disease in humans. Adaptive testing procedures are widely used in single-session assessments for humans with diverse cognitive abilities. In this study, we designed and deployed two up-down staircase assessments for SWM in which 26 pet dogs were required to recall the location of a treat hidden behind one of two identical boxes following delays of variable length. In the first experiment, performance tended to decline with age but few dogs completed the test (n?=?10). However, all of the dogs that participated in the second experiment (n?=?24) completed the assessment and provided reliable evidence of learning and retaining the task. Delay length and age significantly predicted performance supporting the validity of this assessment. The relationships between age and performance were described by inverted U-shaped functions as both old and young dogs displayed deficits in weighted cumulative-scores and trial-by-trial performance. Thus, SWM in pet dogs may develop until midlife and decline thereafter. Exploratory analyses of non-mnemonic fixation strategies, sustained engagement, inhibitory control, and potential improvements for future SWM assessments which adopt this paradigm are also discussed.
相似文献The aim of this article is threefold. First, we seek to elicit the attitudes and practices of middle-aged and elderly Moroccan Muslim women towards ageing and care for the elderly. Second, we aim to identify possible differences between middle-aged and elderly women’s attitudes and practices. Third, we seek to explore which role religion plays in their attitudes and practices. Qualitative empirical research was conducted with a sample of middle-aged and elderly Moroccan Muslim women living in Antwerp (Belgium) (n = 30) and with experts in the field (n = 15). Our study unveils that ageing and care for the elderly are clearly understood from a religious framework. More specifically, theological and eschatological considerations take up a central position. Access to and utilization of professional elderly care is hampered by several barriers (e.g. religious, cultural and financial). We found a more open attitude towards professional elderly care among middle-aged women than among elderly women.
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