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141.
Experiment 1 investigated the controlling properties of variability contingencies on choice between repeated and variable responding. Pigeons were exposed to concurrent-chains schedules with two alternatives. In the REPEAT alternative, reinforcers in the terminal link depended on a single sequence of four responses. In the VARY alternative, a response sequence in the terminal link was reinforced only if it differed from the n previous sequences (lag criterion). The REPEAT contingency generated low, constant levels of sequence variation whereas the VARY contingency produced levels of sequence variation that increased with the lag criterion. Preference for the REPEAT alternative tended to increase directly with the degree of variation required for reinforcement. Experiment 2 examined the potential confounding effects in Experiment 1 of immediacy of reinforcement by yoking the interreinforcer intervals in the REPEAT alternative to those in the VARY alternative. Again, preference for REPEAT was a function of the lag criterion. Choice between varying and repeating behavior is discussed with respect to obtained behavioral variability, probability of reinforcement, delay of reinforcement, and switching within a sequence.  相似文献   
142.
The fixed point combinator (Y) is an important non-proper combinator, which is defhable from a combinatorially complete base. This combinator guarantees that recursive equations have a solution. Structurally free logics (LC) turn combinators into formulas and replace structural rules by combinatory ones. This paper introduces the fixed point and the dual fixed point combinator into structurally free logics. The admissibility of (multiple) cut in the resulting calculus is not provable by a simple adaptation of the similar proof for LC with proper combinators. The novelty of our proof—beyond proving the cut for a newly extended calculus–is that we add a fourth induction to the by-and-large Gentzen-style proof. Presented by Robert Goldblatt  相似文献   
143.
Not only do the writings of Nietzsche – early and late – fail to support the pedagogy of self-reformulation, this doctrine embodies what for him is worst in man and would destroy that which is higher. The pedagogy of self-reformulation is also incoherent. In contrast, Nietzsche offers a fruitful and comprehensive theory of education that, while non-democratic and contemptuous of egalitarian aspirations, emerges consistently from his metaphysics and philosophical anthropology. Whatever, then, we might think of his premises, Nietzsche’s philosophy of education represents an attractive model for those who would develop a meaningful, distinctive, and persuasive educational theory. It defines a domain of the possible and then straightforwardly states what is and is not to be done within it – and why.  相似文献   
144.
We examined the potentially mediating effects of negative affectivity (NA) on the hope–depression relationship among a sample of postpartum women. We also assessed the social support reported by these women and examined the possible mediating effects of NA on the social support–postpartum depression relationship. Correlational analyses of data obtained from women (N = 98) who had given birth in the previous 6 months revealed that NA did not mediate either hope or social support in the prediction of postpartum depression. Hope accounted for a significant degree of variance in postpartum depression. These data suggest that hope has palliative effects among women following childbirth and these effects are not nullified or explained by emotional predispositions.  相似文献   
145.
Over the last years several European patents were opposed for protecting technology violating the morality requirement under Article 53(a) EPC. Attempts have been made by the Appeal Boards of the European Patent Office (EPO), as well as by amendments introduced into the Implementing Regulations of the European Patent Convention (EPC), to address this sensitive patentability requirement more precisely. The most recent hot topic coming up in this context is the patentability of stem cells. It is to be expected that this discussion will still go on in the field of biotechnological inventions for the next several years. An earlier version of this paper was presented at an international conference, “The Ethics of Intellectual Property Rights and Patents,” held in Warsaw, Poland on 23–24 April, 2004.  相似文献   
146.
In World Poverty and Human Rights, Thomas Pogge argues that the global rich have a duty to eradicate severe poverty in the world. The novelty of Pogges approach is to present this demand as stemming from basic commands which are negative rather than positive in nature: the global rich have an obligation to eradicate the radical poverty of the global poor not because of a norm of beneficence asking them to help those in need when they can at little cost to themselves, but because of their having violated a principle of justice not to unduly harm others by imposing on them a coercive global order that makes their access to the objects of their human right to subsistence insecure. In this paper, I claim that although Pogge is right in arguing that negative duties are crucial in an account of global justice, he is wrong in saying that they are the only ones that are crucial. Harming the global poor by causing their poverty provides a sufficient but not a necessary condition for the global rich to have a duty of justice to assist them. After engaging in a critical analysis of Pogges argument, I conclude by suggesting the need for a robust conception of cosmopolitan solidarity that includes positive duties of assistance which are not mere duties of charity, but enforceable ones of justice.  相似文献   
147.
This study evaluated the validity of mediating pathways in predicting self-assessed negative affect from shyness/social withdrawal, peer rejection, victimization by peers (overt and relational), and the attitude that aggression is legitimate and warranted. Participants were 296 3rd through 5th graders (156 girls, 140 boys) from 10 elementary schools. Self-report measures of victimization, attitudes, and negative affect, and a teacher-report measure of shyness/social withdrawal and peer rejection were completed during the spring semesters of 2 consecutive years. Hierarchical regression analyses supported the mediational model in predicting negative affect at Time 2. However, an increase in negative affect over the 12-month study period was best accounted for by direct effects of increased victimization and changes in attitudes/attributions regarding aggression. Implications for the planning of school interventions designed to interrupt these victimization-maladjustment pathways are discussed.  相似文献   
148.
清代中期“以礼代理”说刍议   总被引:1,自引:0,他引:1  
清代中期,以凌廷堪、焦循、阮元为代表的汉学家提出了“以礼代理”说,即主张用礼学代替理学。他们认为,儒学的中心是“礼”而不是“理”,脱离了“礼”而言“理”,只能导致师心自用以及对人的具体情感的漠视。这一学说是清初顾炎武所倡导的学术方向的继续,它把人们的目光由内在精神变革转向对外在制度的关注;同时,这一学说明确反对以抽象化的“理”来约束人们的行为,它在一定程度上减轻了理学所带来的消极影响。  相似文献   
149.
Cognitive defusion techniques are designed to reduce the functions of thoughts by altering the context in which they occur, rather than the attempting to alter the form, frequency, or situational sensitivity of the thoughts themselves. Applied technologies designed to produce cognitive defusion seem to lead to reductions in the believability of negative thoughts, but defusion techniques are generally only parts of complex packages and the role of defusion techniques per se is note yet known. The present study examined the impact of a cognitive defusion technique first described by Titchener nearly 90 years ago: rapidly repeating a single word. In series of eight single-case alternating treatment designs, this defusion technique was compared to a distraction task, and to a thought control task on reductions in the discomfort and believability of self-relevant negative thoughts. The cognitive defusion technique reduced both discomfort and believability more so than the comparison approaches. Control studies showed that the effect was probably not due to demand characteristics.  相似文献   
150.
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   
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