An explanation for the low-temperature H evolution peak in hydrogenated amorphous silicon films deposited 'on the edge of crystallinity'

The puzzling existence of a sharp low-temperature (T = 400°C) H evolution peak in compact hydrogenated amorphous silicon (a-Si : H) films deposited 'on the edge of crystallinity' is examined. From infrared absorption and X-ray diffraction (XRD) measurements, we show that none of the standard methods used to explain the existence of this peak in a-Si : H materials is applicable to the present films. From the Si-H wag-mode peak frequency, we postulate the existence of very small Si crystallites contained within the amorphous matrix. While the crystallite volume fraction is too small to be detected by XRD in the as-grown films, crystallization is observed for this material at anneal temperatures as low as 500°C. It is proposed that these crystallites catalyse the crystallization of the remainder of the amorphous matrix upon moderate annealing, enabling H surface desorption and H₂ out-diffusion to the sample surface along newly formed grain boundaries at low anneal temperatures.     

Changes in the gangliosides of erythrocyte membranes of schizophrenic patients

The pattern of gangliosides in membranes of erythrocytes was examined in healthy donors, in acute schizophrenics without neuroleptic treatment and in alcohol-dependent patients. 7 different gangliosides could be detected after extraction, purification by column chromatography and fractionation by TLC. Healthy donors were characterized by the following pattern of gangliosides: GX = 5.8%, GT1b = 6.7%, FucGD1b = 5.2%, und GD1a = 12.6%, GD3 = 9.2%, SPG = 43.5% and GM3 = 17.0%. In schizophrenic patients the GM3- and GD3-fraction were increased. No difference was found between the control group and the alcoholics.     

Violent delinquency: an examination of psychopathic typologies

This study sought to determine the combined effects of psychopathy, low intellectual functioning, and love deprivation on violent delinquency. Low-intellectual-functioning psychopaths were significantly more violent than were low or high-intellectual-functioning nonpsychopaths or high-intellectual-functioning psychopaths. Love deprivation was more strongly related to violence than was psychopathy/intellectual functioning, and severely love-deprived, low-intellectual-functioning psychopaths were the most violent.     

Gender Differences in the Accuracy of Grade Expectancies and Evaluations

Participants were 131 (69 women, 62 men)students in Introductory Psychology, Social Psychology,and Computer Science courses. Eighty-six percent of thesample was Caucasian. The goals of this study were to assess (a) how accurate students'preexamination expectancies and postexamination gradeevaluations are and whether gender differences in theaccuracy of expectancies and grade evaluations onexaminations exist, (b) whether expected grades predictpostexamination grade evaluations even with actualgrades controlled (self-consistency effect), and (c)whether students' grade expectations and evaluationsbecome more accurate with experience. Throughout thecourse of a semester, students estimated their gradesfor each of their examinations. Students overestimatedtheir grades at all points in the semester, although women in Introductory Psychology overestimatedtheir grades less than men did. Students' expectedgrades were a better predictor of their postexaminationgrade evaluations than were their actual grades. For Introductory Psychology students,expectancies and grade evaluations became more accurateas the semester progressed. The importance of accurateself-perceptions regarding academic performance isdiscussed.