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71.
In the 80's Pierangelo Miglioli, starting from motivations in the framework of Abstract Data Types and Program Synthesis, introduced semiconstructive theories, a family of large subsystems of classical theories that guarantee the computability of functions and predicates represented by suitable formulas. In general, the above computability results are guaranteed by algorithms based on a recursive enumeration of the theorems of the whole system. In this paper we present a family of semiconstructive systems, we call uniformly semiconstructive, that provide computational procedures only involving formulas with bounded complexity. We present several examples of uniformly semiconstructive systems containing Harrop theories, induction principles and some well-known predicate intermediate principles. Among these, we give an account of semiconstructive and uniformly semiconstructive systems which lie between Intuitionistic and Classical Arithmetic and we discuss their constructive incompatibility.  相似文献   
72.
73.
We examined individual and group characteristics associated with the duration of community involvement (i.e., length of residence) in 11 Illinois Oxford Houses for 129 male recovering addicts. Survival analyses indicated that the best predictor of duration of community involvement from demographic items was age (i.e., older age and older age of fellow residents were associated with being more likely to continue residence). Among psychological measures, the best survival predictor was lack of pessimism of the future. Although the relationship between longer length of residence and treatment outcomes are complex, because it is often difficult to keep people involved in treatment programs, knowledge that we can gain about those factors that might lead to greater lengths of stay are of importance.  相似文献   
74.
This study investigated the reinforcing properties, limits, and motivating potentials of sensory stimuli with autistic children. In the first phase of the study, four intellectually retarded autistic children were exposed to three different types of sensory stimulation (vibration, music, and strobe light) as well as edible and social reinforcers for ten-second intervals contingent upon six simple bar pressing responses. In the second phase, the same events were used as reinforcers for correct responses in learning object labels. The results indicated that: (a) sensory stimuli can be used effectively as reinforcers to maintain high, durable rates of responding in a simple pressing task; (b) ranked preferences for sensory stimuli revealed a unique configuration of responding for each child; and (c) sensory stimuli have motivating potentials comparable to those of the traditional food and social reinforcers even when training receptive language tasks.  相似文献   
75.
Two studies examined effects of interventions to reduce noise levels from portable stereo headphones. Study 1 examined the effectiveness of warning signs posted in and nearby public elevators with 567 passengers possessing a portable headphone (total N = 7,811). During a 9-day baseline, the mean percentage of headphones played at an observer-audible level was 85%. During a subsequent 6-day warning sign phase, the mean percentage of audible headphones declined to 59%, which increased to a mean of 76% during a second baseline phase (5 days). Study 2 assessed the impact of a student confederate who lowered his or her observer-audible headphone volume at the polite request of a second student confederate. Of the 4,069 elevator passengers, 433 possessed a portable headset. The mean percentage of observer-audible headphones during a 4-day baseline was 85%. Subsequently, a 5-day modeling intervention reduced audible volumes to a mean of 46%. During a second baseline phase of 4 days, the mean level was 77%, and during reintroduction of the modeling phase (9 days) the mean level was 42%. The modeling intervention was significantly more effective with women (53% compliance) than men (29% compliance).  相似文献   
76.
An experiment is reported in which the reactions of observers to the relative and absolute deprivation of others are assessed. Eighty German and 80 Italian subjects made decisions about ingroup (own nationality) or outgroup (foreign) protagonists suffering high or low relative and absolute deprivation. Results showed that subjects were more likely to take social action that violated some rule when the protagonist was in high rather than low absolute deprivation. Racist subjects were somewhat more likely to satisfy the request of a deprived ingroup protagonist whereas non-racist subjects favoured the deprived outgroup. No differences emerged for non-deprived protagonists. Overall, Germans tended to take social action only when the protagonist suffered high absolute deprivation whereas Italians took action regardless of degree of absolute deprivation. © 1998 John Wiley & Sons, Ltd.  相似文献   
77.
Swiss CD‐1 lactating mice show a different pattern of attack toward intruders of differing sex, displaying defensive attack against the male (bites on the head and ventrum associated with fear) and offensive attack against the female (bites on the back and flanks with no elicitation of fear). This dichotomy may reflect diverse functions of maternal aggression: the attack toward males (the more infanticidal gender in laboratory strains) has been interpreted as a counterstrategy to infanticide, whereas the attack toward females may serve to establish a social hierarchy or to space rivals of the same sex. In terms of proximal mechanisms, fear may be a key factor involved in the modulation of the different patterns of attack. In Experiment 1 we compared the pattern of attack of lactating females in Swiss CD‐1 and Wild mice toward male and female intruders in relation to fear components of behavior of the attacking dams. Results showed that in Swiss mice, male intruders were attacked with a defensive type of attack accompanied by high levels of fear, whereas female intruders did not elicit fear in the attacking animal but were attacked with an offensive pattern. In Wild mice, both types of intruders were attacked with a defensive pattern; notwithstanding, fear was evident only toward male intruders. This suggests that fear is not totally responsible for the expression of the defensive type of attack. To test the hypothesis that defensive attack toward male and female intruders may be related to the infanticidal potential of the intruder, Experiment 2 examined levels of infanticide in both male and female Swiss CD‐1 and Wild mice. Swiss female mice showed virtually no infanticidal behavior, whereas Swiss males and both sexes of Wild mice showed similarly high levels of infanticide (55%–75%). From a game theory perspective, the defensive pattern of maternal attack toward female intruders in Wild mice is discussed as “extreme” defense of a high value resource and thus, functionally, a competitive form of aggression. Aggr. Behav. 26:193–203, 2000. © 2000 Wiley‐Liss, Inc.  相似文献   
78.
Because procrastination concerns a person’s ability to meet deadlines, temporal dimension is clearly important to this personality construct. In the present study, the characteristic profile of arousal and avoidant motives of procrastinators were related to past, present, and future time conceptions. Participants (140 women, 135 men; mean age = 49.4, SD = 5.55) completed measures of arousal and avoidance procrastination, and time orientation. Results indicated that avoidant procrastination was associated negatively with present-fatalistic time orientation, and arousal procrastination was associated positively with present-hedonist and negatively with future time orientations. The variance accounted for by time orientations was modest, yet provides further evidence that there are distinct motives for chronic procrastination.  相似文献   
79.
80.
Chinese society is characterized by emerging fragmentation and by the coexistence of traditional and Western values, goals and norms. In this multifaceted environment bi‐cultural selves, which encompass social and individual orientations, may emerge. The aim of this paper is to explore if features of bi‐cultural selves concerning interactions, emotions, and values are reflected in online public discussions in China. In order to address this question, we explored two of the most popular bulletin board systems (BBSs): Tian Ya and Feng Huang Forums. BBSs attract almost one third of Internet users in China and provide these users with a forum to carry out public dialogue; BBSs are thus an ideal place to study how the self is socially shaped in public communication. A sample of 6109 messages was subjected to quantitative content analysis. Results show that twofold self‐construal, corresponding to the individual‐ and social‐oriented self, are (also) detected in BBSs forum content: direct and polemic content coexist with conciliatory content; ego‐focused and other‐focused emotions are almost equally as frequent as one another; and traditional values are evoked together with the quest for truth and individual rights. Moreover, three typologies of Internet users (proactive, ambivalent, and follower), which were identified on the basis of the quality of their online interactions, show different patterns of emotions and values. We may thus conclude that alternative ways of constructing self‐other and self‐society relationships currently coexist in China and that these alternative views confront each other on BBS forums.  相似文献   
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