Development of self-handicapping tendencies.

This study was undertaken to determine when U.S. children begin to self-handicap, that is, to reduce preparation effort before evaluations rather than applying themselves to do their best. The personal variables examined for their impact on practice behavior were gender, grade level, and self-esteem. The situational variables were time of the self-esteem test (before or after the evaluation task) and importance of the evaluation task. The results showed that (a) the 6th-grade boys were more likely than the 6th-grade girls to self-handicap, (b) the 3rd-grade children were not as affected as the 6th-grade children by the self-evaluation implications of performance evaluations, (c) self-handicapping by low-self-esteem and high-self-esteem 6th graders depended on recent experiences, and (d) the self-affirming experience of a self-esteem test reduced the motivation to self-handicap among high-self-esteem 6th-grade boys.

Effectiveness of counteraggression strategies in reducing interactive aggression by males.

Studies on techniques of reducing aggression have typically examined passive, matching, and punitive strategies of counteraggression and have been remarkably inconsistent in their findings. This research was designed to resolve the contradictory results by reconceptuallzing the strategies in terms of counteraggression/aggression (cA/A) ratios. We predicted that the norm of reciprocity and the tendency to exploit weakness would make a cA/A ratio of less than but close to 1.0 (matching) most effective in reducing aggression. Ten cA/A ratios were used. One hundred male subjects set punishment level set by their opponent (a confederate) on 25 trials, and, on 13 losing trials, received punishment. The most effective cA/A ratios for reducing aggression were the lowest ones. Lower cA/A ratios reduced aggression and ratios greater than 1.0 increased aggresion. Contrary to the results of previous studies, the matching strategy was ineffective in reducing aggresion.

N-nitrosomorpholine and N-nitrosobutylamine-stimulated DNA synthesis in BHK-21/C13 cells.

Non-semiconservative DNA synthesis was examined in BHK-21/C13 cells after treatment with the aliphatic N-nitrosobutylamine (NB) and the heterocyclic N-nitrosomorpholine (NM). The extent of repair synthesis after alkylation was compared quentitatively and calculations were made of the amount of DNA damage per cell and number of bases inserted per damaged site. Of the chromosome aberrations caused by NM the most predominant were dicentrics. Other aberrations included fragments, gaps, breaks and exchanges of both the chromatid and chromosome type. Unlike NM, NB elicted a higher frequency of chromatid breaks.

Rapid, sensitive assay for staphylococcal enterotoxin A by reversed immuno-osmophoresis.

Reversed immuno-osmophoresis using phenylsulfonated immune gamma(2)-globulin is a rapid sensitive method of assaying for staphylococcal enterotoxin A. The technique is compared with other serological methods.

Comparison of the fatty acids of proteolytic type B and nonproteolytic types E and F of Clostridium botulinum.

Lipids were extracted from vegetative cells and spores of Clostridium botulinum. The total lipids extracted averaged approximately 3.8% of the dry weight of vegetative cells and 2.5% of the dry weight of spores of types 61E, "F," and 115B. The fatty acids were analyzed in the form of their methyl esters by gas-liquid chromatography. Infrared spectroscopy, mercuric acetate fractionation, and silver nitratethin layer chromatography served as complementary means of analysis. The total fatty acids included straight chain, saturated, unsaturated, and cyclopropane acids. Hexadecanoic and tetradecanoic acids were the predominant acids in both the spores and vegetative cells. Together, they comprised over 50% of the total fatty acids. Unsaturated acids were the second major group. These were primarily 7,8-tetradecenoic, 9,10-hexadecenoic, 7,8-hexadecenoic, 11,12-octadecenoic, and 9,10-octadecenoic acids. Nonproteolytic types 61E and "F" possessed an 18-carbon diunsaturate, which was not found in the vegetative cells or spores of proteolytic type 115B. A mechanism for the synthesis of unsaturated and cyclopropane acids was proposed.