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To understand how individuals adapt to and anticipate each other in joint tasks, we employ a bidirectional delay–coupled dynamical system that allows for mutual adaptation and anticipation. In delay–coupled systems, anticipation is achieved when one system compares its own time‐delayed behavior, which implicitly includes past information about the other system’s behavior, with the other system’s instantaneous behavior. Applied to joint music performance, the model allows each system to adapt its behavior to the dynamics of the other. Model predictions of asynchrony between two simultaneously produced musical voices were compared with duet pianists’ behavior; each partner performed one voice while auditory feedback perturbations occurred at unpredictable times during live performance. As the model predicted, when auditory feedback from one musical voice was removed, the asynchrony changed: The pianist’s voice that was removed anticipated (preceded) the actions of their partner. When the auditory feedback returned and both musicians could hear each other, they rapidly returned to baseline levels of asynchrony. To understand how the pianists anticipated each other, their performances were fitted by the model to examine change in model parameters (coupling strength, time‐delay). When auditory feedback for one or both voices was removed, the fits showed the expected decrease in coupling strength and time‐delay between the systems. When feedback about the voice(s) returned, the coupling strength and time‐delay returned to baseline. These findings support the idea that when people perform actions together, they do so as a coupled bidirectional anticipatory system.  相似文献   
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Do the conditions under which promises are made determine whether they ought to be kept? Philosophers have placed a number of conditions on promising which, they hold, must be met in order to make promise-keeping obligatory. In so doing, they have distinguished valid promises from invalid promises and justified promises from promises that are not justified. Considering such conditions, one by one, we argue that they are mistaken. In the first place, the conditions they lay down are not necessary for either valid or justified promise-making. In the second place, promises need not meet such conditions in order to create moral obligations. In general, such analyses of promising fail because they suffer from a confusion between promise-making and promise-keeping. Philosophers have wrongly supposed that obligations to keep promises are dependent upon, or derivable from, the quality of the promises themselves, at the time they are made, instead of focusing on conditions that must be satisfied at the time when promises are supposed to be kept. It is not the quality of a promise that determines an obligation to keep it but the rightness or wrongness of performing the promised act.  相似文献   
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OBJECTIVE: This report reviews the evidence that informs the role of health and mental health care providers in addressing youth smoking cessation. DESIGN: Qualitative literature review. RESULTS: Physicians do not consistently screen adolescents for tobacco use and fail to provide recommended cessation advice. Challenges to addressing smoking cessation include the need for procedures to ensure confidentiality and the existence of competing demands to provide other services. Few published studies have specifically addressed the effectiveness of clinical interventions. Interventions that require return visits or follow-up phone contacts are technically difficult to implement in this population. Successful interventions may require resources not available in nonresearch settings. Most studies have used brief clinical intervention as a control condition, making it impossible to evaluate its effectiveness. CONCLUSION: There is little evidence that supports current clinical smoking cessation guidelines for adolescents. More research is needed to develop inexpensive, efficient clinical interventions that can provide youths access to smoking cessation help. Future challenges include reorganizing clinical systems to offer greater counseling by support staff or in electronic formats and to provide effective booster messages and follow-up care in a population that is difficult to track.  相似文献   
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Elka Klein’s writings have illuminated reciprocal and distinctive characteristics of the social and intellectual lives of Jewry in Iberia and by comparison Northern Europe during the High Middle Ages. This article honors her insights, by comparing the development of biblical hermeneutics at the Abbey of St. Victor in Paris and in the writings of Abraham ibn Ezra. Hugh of St. Victor’s introduction to the study of Scripture, Didascalicon, provides a program for the individual student to integrate all branches of human knowledge into the search for Divine Wisdom that may be found only in Scripture. The innovation in Hugh’s program is the emphasis on the “literal” or “historical” sense of Scripture as the solid basis for the development of theological study. Grammar and rhetoric were stepping stones that led the young theologians to higher levels of Divine Wisdom. The introduction to Abraham ibn Ezra’s commentary on the Pentateuch constitutes a parallel point of orientation for twelfth-century Jewish readers. A close reading of ibn Ezra’s prologue maps the hermeneutical approaches that different communities – Christian, rabbinic Jewish, and Karaite – utilized in their expositions of the Pentateuch. After critiquing each community, ibn Ezra offers his own approach that builds an overall framework for correct interpretation on the foundation of grammar and the rabbinic oral tradition. From this perspective, the article demonstrates that during this period Jews and Christians, both in Iberia and Northern Europe, focused on harmonizing reason and revelation. Both communities used grammar as the primary criterion for evaluating the accumulation of traditional sources. Both approaches intended to develop students, who were capable of understanding that “reason is the angel that mediates between God and humanity.”  相似文献   
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Pregnancy reflects a common experience for women in today's workforce, yet recent data suggest that some women scale back or leave the workforce following childbirth. Considering these effects on women's careers, researchers have sought to understand the underlying dynamics of these decisions. Here, we explore a paradoxical reason for weakened postpartum career attitudes: help that women receive during pregnancy. We integrate stereotype threat and benevolent sexism theories to explain how the effects of help on postpartum intentions to quit may be transmitted through reductions in work self-efficacy. In doing so, we consider the role of perceived impact—or the extent to which help interferes with versus enables women's perceived ability to continue performing their work role. Results of a weekly diary study of 105 pregnant employees suggest that work-interfering help led to decreased self-efficacy for work during the following week. Furthermore, there was an indirect effect of average help received at work during pregnancy on postpartum intentions to quit the workforce through reductions in work self-efficacy that was stronger insofar as help was work-interfering versus work-enabling. Taken together, our results highlight unintended negative consequences that occur when others provide ineffective support to women at work during pregnancy.  相似文献   
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