This note illustrates that a combination of the approach in our previous papers (Boucherie and Boxma, 1996, Probability in the Engineering and Informational Sciences10: 261–277; Jain and Sigman, 1996, Probability in the Engineering and Informational Sciences 10: 519–531) directly leads to a Pollaczek-Khintchine form for the workload in a queue with negative customers. The same technique is also applied to risk processes with lump additions.

Children exposed to alcohol prenatally have been found to be at risk for developmental and behavioral problems; however, the relation between maternal alcohol consumption and other environmental factors has not been fully explored in the literature. In this study, subjects were 44 firstborn infants of women over 30 years of age. Structural equation modeling was used to test the hypothesis that maternal alcohol use during pregnancy was related to infant negative affect. Furthermore, negative affect was assumed to influence the mother-infant relationship. It was hypothesized that mothers of infants exhibiting negative affect would be less positive in interaction and that insecure infant attachment behavior would be more prevalent in these infants. Results of model testing confirmed the hypothesis. In addition, maternal alcohol consumption following pregnancy was not found to influence significantly either maternal interaction or infant attachment behavior.

The dielectric response in artificially layered 1x1 KTaO3/KNbO3 perovskite superlattice structures is reported. While KTaO3 and KNbO3 are ferroelectric or paraelectric, respectively, superlattices appear antiferroelectric based on an increase in dielectric constant with applied dc bias. This “positive tunability” in dielectric response occurs at the same temperature region where a structural phase transition is observed. This dielectric behavior is inconsistent with the nonlinear response for either paraelectric or ferroelectric materials. However, an increase in the dielectric constant with applied electric field is consistent with antiferroelectric behavior. The antiferroelectric ordering correlates with cation modulation imposed by the superlattice.