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61.
In a two-stimulus matching paradigm requiring “same” and “different” responses to simple geometric dimensions, the successive stimulus presentation mode with several retention intervals was compared to a simultaneous stimulus presentation mode. For the simultaneous condition, the data suggested a wholistic template matching process, but in none of the successive conditions was template matching indicated. The retention interval of the successive condition allows the subject to analyze out the target dimension from the first two-dimensional stimulus. The ability to anticipate the value of the target dimension in the second stimulus could also influence the representation of the first stimulus. The findings shed some light upon the perceptual interactions between dimensions that constitute the stimulus. In particular, an outside-to-inside order of iconic scanning appeared to be supported by the data.  相似文献   
62.
Signalled free-operant avoidance of shock by pigeons pecking a key   总被引:1,自引:1,他引:0       下载免费PDF全文
Two pigeons were trained to peck a key under a free-operant avoidance schedule. Then, changes in key color signalled the beginning (safe period) and the end (warning period) of the response-shock interval, with a response required to change the key color. Finally, a change in key color signalled the warning period and either a response or a shock reinstated the safe stimulus. During signalled avoidance, response rate was higher during the warning stimulus than during the safe stimulus. More responding tended to occur in the warning stimulus when it was terminated by either a response or a shock than by only a response. In either procedure, response latency during the warning stimulus was a function of the duration of the warning stimulus. In general, response and shock rate were higher during unsignalled than during signalled avoidance. When the warning stimulus was brief, the results were similar to those of unsignalled avoidance. These results confirm previous findings with pigeons, are in general agreement with data provided by other species in studies of signalled avoidance, and thereby indicate the transituationality of the key-pecking operant.  相似文献   
63.
The electronic structures of anionic, imidic and amidic forms of sulphonamides were investigated and compared by means of I.R., Raman and U.V. spectroscopy. Indices reflecting the electronic situation of the common moiety p-H2N-C6H4-SO2 was a whole, although not necessarily related, physically, to any event taking place in the biological processes, were found to correlate with the in vitro bacteriostatic activity of the specific individual forms. The influence of N1-substituents both on the SO2 electronic features and on the coupling between the para amino group and the phenyl ring was discussed. It resulted that the most active chemical species, in this class of compounds, are characterized, electronically, by the most electron-rich common moiety and, in particular, by the most negative oxygens in the SO2 group and the most available (less engaged) lone-pair in the rho-amino group. These conclusions give a new settlement both to the problem of resonance and to the relation between resonance effects and bacteriostatic activity in this class of compounds.  相似文献   
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This study is an investigation of the relationship between third grade final marks, achievement test scores, and subsequent achievement in elementary and secondary school. It was focused on the early identification of students for whom changes in the curriculum might be indicated.  相似文献   
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Adolescents experiencing social anxiety often engage in safety behaviors―covert avoidance strategies for managing distress (e.g., avoiding eye contact)―that factor into the development and maintenance of their concerns. Prior work supports the psychometric properties of the Subtle Avoidance Frequency Examination (SAFE), a self-report survey of safety behaviors. Yet, we need complementary methods for assessing these behaviors within contexts where adolescents often experience concerns, namely, interactions with unfamiliar peers. Recent work indicates that, based on short, direct social interactions with adolescents, individuals posing as unfamiliar peers (i.e., peer confederates) and without assessment training can capably report about adolescent social anxiety. We built on prior work by testing whether we could gather valid SAFE reports from unfamiliar untrained observers (UUOs), who observed adolescents within archived recordings of these short social interactions. A mixed clinical/community sample of 105 adolescents self-reported on their functioning and participated in a series of social interaction tasks with peer confederates, who also provided social anxiety reports about the adolescent. Based on video recordings of these tasks, trained independent observers rated adolescents’ observed social skills, and an additional set of UUOs completed SAFE reports of these same adolescents. Unfamiliar untrained observers’ SAFE reports (a) related to adolescents’ SAFE self-reports, (b) distinguished adolescents on clinically elevated social anxiety concerns, (c) related to trained independent observers’ ratings of adolescent social skills within interactions with peer confederates, and (d) related to adolescents’ self-reported arousal within these same interactions. Our findings support use of unfamiliar observers’ perspectives to understand socially anxious adolescents’ interpersonal functioning.  相似文献   
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The sociological literature has produced a remarkably consistent picture of the quantitative patterns of religious disaffiliations in Western countries. This article argues, and demonstrates, that strong changes in a social context may lead individuals to disaffiliate rapidly, leading to very different aggregate effects from those in the “western model.” We use the unique situation of the separation of Germany from 1949 to 1989 and its subsequent reunification as a “natural experiment” to show just how much the relationships routinely found can be disrupted under changed conditions. The state socialist “treatment” affected religious disaffiliations in East Germany profoundly as it (a) made disaffiliations 10 times more probable in the East than in the West in the 1950s and 1960s, (b) shielded East German church members from factors that led to mass disaffiliations in the West in the late 1960s and early 1970s, (c) reversed the education‐disaffiliation link in the East, thus making disaffiliation more likely among the less educated, and (d) led to an especially strong increase in disaffiliations in the East right after the reunification  相似文献   
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