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51.
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 review illustrates the role of preimaginal experiences in four main aspects of insect life: feeding, habitat choice, host selection, and social relationships. After an illustration of the two former aspects with examples taken from various species, special attention is paid to the two latter aspects. First, an experiment is described, which demonstrates the existence of preimaginal induction involved in host selection by the solitary parasitoid wasp Dinarmus basalis (Hymenoptera: Pteromalidae). Then, a review of preimaginal induction in ants' behaviour is presented; orientation of social behaviour, particularly altruism, is mainly determined by preimaginal imprinting. All the examples developed in this review clearly show that insects can no longer be considered as strictly, rigidly “pre-programmed” beings. Their complex behavioural development and plasticity is clearly documented.  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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