Purdue Research Foundation

Current techniques for examining the global creation and repair of DNA double-strand breaks are restricted in their sensitivity, and such techniques mask any site-dependent variations in breakage and repair rate or fidelity. We present here a system for analyzing the fate of documented DNA breaks, using the MLL gene as an example, through application of ligation-mediated PCR. Here, a simple asymmetric double-stranded DNA adapter molecule is ligated to experimentally induced DNA breaks and subjected to seminested PCR using adapter and gene-specific primers. The rate of appearance and loss of specific PCR products allows detection of both the break and its repair. Using the additional technique of inverse PCR, the presence of misrepaired products (translocations) can be detected at the same site, providing information on the fidelity of the ligation reaction in intact cells. Such techniques may be adapted for the analysis of DNA breaks introduced into any identifiable genomic location.

SummaryDrastic changes in the role of the foreman during the last few decades are traced to scientific management trends and the growth of industrial unions. Many companies have taken steps to further modify that role, but have necessarily done so with minimum empirical evidence. The research reported here is the first phase of a study designed to throw some light on the effect of a foreman's identification with management on two aspects of his supervisory effectiveness–work group productivity and employee attitude toward the foreman.A measure of management identification was developed for use in studying these effects of the foreman's role in management. Because of the ego‐involved nature of management identification, the measure was based on an indirect method, the Error‐Choice or Direction of Perception technique of attitude measurement. Questions were written on a rational basis to measure management identification and an a priori scoring key was derived. A sample of 212 first line foremen from seven manufacturing plants in Illinois and Michigan completed the experimental questionnaire. The management identification questions were item analyzed for internal consistency and 30 items were selected; none of the Error‐Choice questions had its a priori scoring direction reversed by the item analysis. The reliability estimate of these items was .65 for this group.A sample of 45 corporation executives also completed the questionnaire. This group scored significantly higher on the 30 items than did the 212 foremen, thus providing evidence for the validity of the measuring instrument.The second article in this series will report the relationships found between this measure of foreman identification with management, work group productivity, and employee attitude toward the foreman. The third and final article will present and discuss some secondary correlates of foreman identification with management.

this cycle the residual water had a U/ sub 3/O/sub 8/ concentratioa of 10 mg/l, and a recovery rate from the feed solution of 98.5%. The ion exchanger capacity can be increased by increas~ng the concentration of the feed. The fixation of silicon by the resins necessitates periodic washing with 5% NaOH. (J.S.R.)