Assessing the relationship between adverse childhood experiences and life satisfaction, psychological well-being, and social well-being: United States Longitudinal Cohort 1995-2014.

BACKGROUND: More than half of the U.S. population has experienced adverse childhood experiences (ACE), which are linked to physical and mental health issues. This study examines the relationship between ACEs and life satisfaction, psychological well-being, and social well-being. METHODS: Data of 6323 participants from three waves of the Midlife Development in the United States (1995-1996, 2004-2006, and 2011-2014) were used. Repeated measures models were used to test the associations between ACEs and all three psychosocial scales. Generalized estimating equations (GEE) were used to account for multiple survey measures. Adjusting for demographics and survey wave, GEE models were run for each ACE construct. RESULTS: After controlling for demographic covariables, those reporting an ACE had significantly lower levels of life satisfaction (ß = - 0.20, 95% CI - 0.26 to - 0.15) compared to those without an ACE. Those reporting higher ACE counts were associated with lower life satisfaction compared to those with no ACE (ß = - 0.38, 95% CI - 0.56 to - 0.20; ß = - 0.36, 95% CI - 0.46 to - 0.27; and ß = - 0.13, 95% CI - 0.19 to - 0.08 for ACE counts of 3, 2, and 1, respectively). Abuse (ß = - 0.41, 95% CI - 0.48 to - 0.33) and household dysfunction (ß = - 0.18, 95% CI - 0.25 to - 0.10) were associated with significantly lower life satisfaction. Overall, those exposed to ACEs had significantly lower sense of social well-being. CONCLUSION: In this sample of adults, ACEs were significantly associated with lower life satisfaction, lower psychological well-being, and lower social well-being, especially for those who report abuse and household dysfunction during childhood.

Elliptically polarized high-order harmonic emission from molecules in linearly polarized laser fields.

We perform an accurate polarimetry measurement of high-order harmonic emission from aligned molecules. We find that harmonic emission from N2 can be strongly elliptically polarized even when driven by linearly polarized laser fields. These data have broad implications for understanding molecules in strong fields because they cannot be explained by simple theories based on the strong field approximation and single active electron models. Finally, this work also shows that it is possible to engineer the polarization properties of harmonic emission by carefully preparing a molecular medium.

Molecular recollision interferometry in high harmonic generation.

We use extreme-ultraviolet interferometry to measure the phase of high-order harmonic generation from transiently aligned CO(2) molecules. We unambiguously observe a reversal in phase of the high-order harmonic emission for higher harmonic orders with a sufficient degree of alignment. This results from molecular-scale quantum interferences between the molecular electronic wave function and the recolliding electron as it recombines with the molecule, and is consistent with a two-center model. Furthermore, using the combined harmonic intensity and phase information, we extract accurate information on the dispersion relation of the returning electron wave packet as a function of harmonic order. This analysis shows evidence of the effect of the molecular potential on the recolliding electron wave.

Phase matching, quasi-phase matching, and pulse compression in a single waveguide for enhanced high-harmonic generation.

We demonstrate, for the first time to our knowledge, that the efficient region of high-harmonic generation can be shifted from lower to higher photon energies by combining phase matching, quasi-phase matching, and pulse compression in a single gas-filled waveguide. An intrawaveguide pulse compression process that works through a combination of ionization-induced refraction and guiding shortens the laser pulse as it propagates through an Ar-filled waveguide. This leads to enhanced harmonic emission at high photon energies near 95 eV while it reduces emission at low photon energies near 45 eV. The waveguide geometry also mitigates ionization-induced refraction, allowing Ar gas with high effective nonlinear susceptibility to be used.

High-order harmonic generation up to 250 eV from highly ionized argon.

We demonstrate the generation of very high-order harmonics, up to 250 eV, using argon gas. This extends by 100 eV the highest harmonics previously observed using Ar and exceeds the energies observed using any other medium besides helium. This advance is made possible by using a waveguide geometry to limit plasma-induced laser beam defocusing, making it possible to generate high harmonics from Ar ions. This work shows that high harmonic emission from ions can extend laser-based coherent up-conversion into the soft x-ray region of the spectrum.

Coherent soft x-ray generation in the water window with quasi-phase matching.

We demonstrate enhanced generation of coherent light in the "water window" region of the soft x-ray spectrum at 4.4 nanometers, using quasi-phase-matched frequency conversion of ultrafast laser pulses. By periodically modulating the diameter of a gas-filled hollow waveguide, the phase mismatch normally present between the laser light and the generated soft x-ray light can be partially compensated. This makes it possible to use neon gas as the nonlinear medium to coherently convert light up to the water window, illustrating that techniques of nonlinear optics can be applied effectively in the soft x-ray region of the spectrum. These results advance the prospects for compact coherent soft x-ray sources for applications in biomicroscopy and in chemical spectroscopy.