The predictive validity of teacher nominations: A five-year followup of at-risk youth

The purpose of this study was to examine the predictive validity of a teacher nomination procedure for identifying at- risk children. Two hundred and twenty-five children were nominated by their teachers as well- adjusted (n= 75), socially withdrawn (n=76), or socially aggressive (n=74) during the fourth grade. Five years later, 198 of these children (88%) were located and their adjustment evaluated. Significant differences among the nominated children were found on a variety of measures, including academic grades, sociometric status, and social behavior. In addition, differences in school dropout and delinquent offenses were noted. Results are discussed in terms of the validity of teacher nomination procedures and their utility in identifying at- risk youth.     

Directed forgetting in pigeons resulting from the reallocation of memory-maintaining processes on forget-cue trials

When procedural artifacts are controlled, it has been difficult to demonstrate directed forgetting in pigeons. However, previous research with pigeons has not allowed for the reallocation of working memory (from forget items to remember items) on forget-cued trials as is possible in human directed forgetting experiments. In the present experiment, directed forgetting was found while controlling for procedural artifacts and allowing the pigeons to reallocate memory resources on forget trials. The results indicate that under these conditions, pigeons have active control over memory processing.     

Whose Gene Is It? A Case Discussion About Familial Conflict over Genetic Testing for Breast Cancer

A multidisciplinary group of genetic and other professionals discuss a complex case of familial conflict over access to genetic information. One twin wishes to know the results of her deceased mother's tests for BRCA1 mutations; a second twin objects to researchers making this information available. As the case discussion unfolds, the apparent facts of this case are called into question and the lines of ethical certainty become less clear.     

Reversal of Relative Thresholds for Synaptic Facilitation and Increased Excitability Induced by Serotonin and Tail Nerve Stimulation inAplysiaSensory Neurons

Tail shock induces reflex sensitization inAplysiaand, in parallel, induces a number of modulatory effects in central neurons, such as increased excitability in tail sensory neurons (SNs) and facilitation of synaptic transmission from SNs to motor neurons. Both of these modulatory effects are mimicked by exogenous application of serotonin (5HT) or electrical stimulation of the tail nerve P9. In the present study we examined the activation thresholds for increased excitability and synaptic facilitation induced by either 5HT or P9 stimulation. We found that the concentration of 5HT sufficient to produce a significant increase in excitability produced no significant synaptic facilitation and, conversely, that the intensity of nerve stimulation sufficient to produce significant synaptic facilitation produced no excitability changes. This reversal of relative thresholds for these modulatory effects may reflect the differential access of exogenous 5HT and endogenous 5HT (released by tail nerve stimulation) to the SN cell body and synaptic terminals, respectively.     

Isoluminance and contingent color aftereffects

In the typical induction of the orientation-contingent color aftereffect (CCAE), the stimuli are composed of elements that differ in both color and luminance. Three experiments are reported that show that chromatic contrast between stimulus elements is insufficient for the induction of the orientation-CCAE and that luminance contrast is necessary. These experiments expand on previous research concerned with the role of luminance contrast in the induction of orientation-CCAEs by eliminating alternative explanations.     

Causal Attributions for Poorly Performing Projects: Their Effect on Project Continuation Decisions

This study examined the escalation problem within an attribution theory framework. Students read a case scenario containing causal attribution information that described a poorly performing project under their supervision. They made estimates of its future success, as well as a decision whether to continue it. Perceived stability of causality had the primary effect on expectancy of success. A project whose performance downturn was attributed to a stable cause had a lower expectancy. Locus of causality had a smaller but still significant effect. Project downturns attributed to internal causes had a lower expectancy. Expectancy of success was significantly correlated with project continuation decisions. Discrepancies between these results and those reported by Staw and Ross (1978) are accounted for in terms of Weiner's (1985, 1986) attributional analysis.     

De Re Language,De Re Eliminability,and the Essential Limits of Both

De re modality is eliminable if there is an effective translation of all wffs into non-de re equivalents. We cannot have logical equivalence unless logic has odd theses, but we can have material equivalence by banning all essences, something the non-de re facts let us do, or by giving everything such humdrum essences as self-identity and banning the more interesting ones. Eliminability cannot be got from weaker assumptions, nor independent ones of even modest generality. The net philosophical import is that, quite apart from the merits of essentialism, de re language has scant utility.