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Self-enhancement is variously portrayed as a positive illusion that can foster health and longevity or as defensive neuroticism that can have physiological-neuroendocdne costs. In a laboratory stress-challenge paradigm, the authors found that high self-enhancers had lower cardiovascular responses to stress, more rapid cardiovascular recovery, and lower baseline cortisol levels, consistent with the positive illusions predictions and counter to the predictions of the defensive neuroticism position. A second set of analyses, replicating the 'illusory mental health paradigm' (J. Shedler, M. Mayman, & M. Manis, 1993), also did not support the defensive neuroticism hypothesis. The association between self-enhancement and cortisol was mediated by psychological resources; analyses of the cardiovascular results provided no definitive mediational pathway. Discussion centers on the potential stress-buffering effects of self-enhancing beliefs.

Research has variously portrayed self-enhancement as an indicator of narcissistic defensiveness or as a concomitant of mental health. To address this controversy, the present study used multiple measures of self-enhancement along with multiple measures and judges of mental health, comprehensively assessing their relationship. The results indicated that self-enhancement is positively associated with multiple indicators of mental health and with a more favorable impact on others. Discussion centers on a reconciliation of discrepant portraits of the self-enhancer.

This work describes the design and validation of an instrument to measure the kinetic energies of ions ejected by the pulsed laser ablation (PLA) of a solid target. Mass spectra show that the PLA of Ni, Al, and ZnO targets, in vacuum, using the second harmonic of a Nd:YAG laser (532 nm, pulse duration ∼10 ns) generates abundant Xn+ ions (n≤3 for Ni, ≤2 for Al, ≤3 and ≤2 for Zn and O respectively from ZnO). Ions are selected by their mass/charge (m/z) ratio prior to the determination of their times of flight. PLA of Ni has been studied in most detail. The mean velocities of ablated Nin+ ions are shown to follow the trend v(Ni3+)>v(Ni2+)>v(Ni+). Data from Ni2+ and Ni3+ are fitted to shifted Maxwellian functions and agree well with a model which assumes both thermal and Coulombic contributions to ion velocities. The dependence of ion velocities on laser pulse energy (and fluence) is investigated, and the high energy data are shown to be consistent with an effective accelerating voltage of ∼90 V within the plume. The distribution of velocities associated with Ni3+ indicates a population at cooler temperature than Ni2+. [ABSTRACT FROM AUTHOR]

The experimental and modeling studies of the gas-phase chemistry occurring in dilute, hot filament activated [B.sub.2][H.sub.6]/[H.sub.2] and [B.sub.2][H.sub.6]/C[H.sub.4]/[H.sub.2] gas mixtures are presented. The modeling has revealed rapid interconversion between the various B[H.sub.x] (x = 0-3) species through successive H-shifting reactions and has indicated concomitant H atom loss as the main reason for the reduction in the B atom density upon C[H.sub.4] addition to HF activated dilute [B.sub.2][H.sub.6]/[H.sub.2] gas mixtures.

A harsh early family environment is related to mental and physical health in adulthood. An important question is why family environment in childhood is associated with these outcomes so long after its initial occurrence. We describe a program of research that evaluates a model linking these variables to each other. Specifically, we hypothesize that low social competence and negative emotional states may mediate relations between a harsh early family environment and physiological/neuroendocrine responses to stress, as well as long-term health outcomes. We report evidence that the model characterizes self-rated health, cortisol responses to stress, and, in males only, elevated cardiovascular responses to stress. We discuss how the social context of early life (such as SES) may affect the family environment in ways that precipitate adverse health consequences. Perspectives on comorbidities in physical and mental health are discussed.

The article focuses on a framework for interactive molecular dynamics in a multiuser virtual reality (VR) environment. It refers to a series of controlled studies, which found that sophisticated molecular modeling tasks could be completed more quickly by users within the interactive VR environment than they can using conventional interfaces.

Experimental and modeling studies of the gas-phase chemistry occurring in dilute, hot filament (HF) activated B2H6/H2 and B2H6/CH4/H2 gas mixtures are reported. Spatially resolved relative number densities of B (and H) atoms have been measured by resonance enhanced multiphoton ionization methods, as a function of process conditions (e.g. the HF material and its temperature, the B2H6/H2 mixing ratio, and the presence (or not) of added CH4). Three-dimensional modeling of the H/B chemistry prevailing in such HF activated gas mixtures using a simplified representation of the gas phase chemistry succeeds in reproducing all of the experimentally observed trends, and in illustrating the key role of the "H-shifting" reactions BHx + H ⇌ BHx-1 + H2 (x = 1−3) in enabling rapid interconversion between the various BHx (x = 0−3) species. CH4 addition, at partial pressures appropriate for growth of boron-doped diamond by chemical vapor deposition methods, leads to ∼30% reduction in the measured B atom signal near the HF. The modeling suggests that this is mainly due to concomitant H atom depletion near the HF, but it also allows us a first assessment of the possible contributions from B/C coupling reactions upon CH4 addition to HF activated B2H6/H2 gas mixtures. [ABSTRACT FROM AUTHOR]