The natural sampling of airborne trace signals from explosives concealed upon the human body.

An experimental study of the natural sampling of trace signals from explosives concealed upon the human body was performed by taking proper account of the thermal behavior of the air surrounding the human body and the particles therein. Experiments were conducted in a dispersal chamber to identify variables affecting the detectibility of concealed RDX and TNT patches. Movement by human volunteers was found to enhance the available explosive trace signal above a baseline level. Clothing blocked some of this movement-generated trace signal. The detected signal levels were also found to vary significantly from volunteer to volunteer, indicating that human variability is an issue in explosive trace detection. Further, under the conditions studied here, the detectibility of RDX and TNT was dependent upon the efficient sampling of contaminated particulate matter, not the vapor phase. The present results are now being applied to the design of a practical, nonintrusive trace detection portal for aviation security screening and related applications.     

Problematic police performance and the personality assessment inventory

A relative newcomer to personality assessment in the area of law enforcement is the Personality Assessment Inventory, or PAI. Earlier MMPI research in the area of police selection has focused upon antisocial behavior, control of aggression, and validity indices, particularly the L scale. In this study T scores for 800 male and female police officer candidates on the PAI scales Negative Impression (NIM), Positive Impression (PIM), Antisocial-Antisocial Behaviors (ANTA), Antisocial-Egocentricity (ANTE), and Antisocial-Stimulus Seeking (ANTS) were used as predictors of the criterion variables Insubordination, Excessive Citizen Complaints, and Neglect of Duty. Highly significant coefficients were obtained for ANTE as a predictor of Insubordination and Excessive Citizen Complaints. For Neglect of Duty, two significant coefficients were obtained, one for ANTS and another for NIM. Discussion centered on the fact that egocentricity is a predictor of Insubordination and Excessive Citizen Complaints, and Neglect of Duty is related to stimulus seeking. Authors' Note: William U. Weiss, Ph.D., is a professor in the Department of Psychology, The University of Evansville, 1800 Lincoln Avenue, Evansville, IN 47722. Sarah Zehner is an undergraduate psychology major at The University of Evansville. Robert Davis, Ph.D., is executive vice-president and director of science, research, and development for Matrix, Inc., and Cary Rostow, Ph.D., is president of Matrix, Inc., Baton Rouge, LA. Emily DeCoster-Martin was an undergraduate psychology major at The University of Evansville at the time this paper was written.