These results support the hypothesis that gender differences in rates of depression in the general population are, to a considerable extent, a consequence of role differences.

This work investigates the fundamental nature of sulfur mustard surface adsorption by characterizing interfacial hydrogen bonding and other intermolecular forces for the surrogate molecule (simulant) 2-chloroethyl ethyl sulfide (2-CEES). Adsorption at the surface of amorphous silica is the focus of this work because of silica’s low chemical reactivity, well-known properties, and abundance in the environment. 2-CEES has two polar functional groups, the chloro and thioether moieties, available to accept hydrogen bonds from free surface silanol groups. Diethyl sulfide and chlorobutane are also investigated to independently assess the role of the chloro and thioester functionalities in the overall adsorption mechanism and to explore the interplay between the charge transfer and electrostatic contributions to total hydrogen-bond strength. Our approach utilizes infrared spectroscopy to study specific surface–molecule interactions and temperature-programmed desorption to measure the activation energy for desorption of adsorbed molecules. Our results indicate that 2-CEES adsorbs to silica by hydrogen bonding through either the chloro or thioether moieties but is unable to form a more stable configuration in which both polar groups interact simultaneously with adjacent silanol groups. The activation energy for desorption of 2-CEES is nearly 43 kJ/mol, driven by both strong hydrogen bonding and other non-bonding interactions. A systematic study of chloroalkanes reveals that each methylene group contributes approximately 5–8 kJ/mol to the overall desorption energy.

Women's greater risk of depression is one of the most consistent findings in psychiatric epidemiology. However, the explanation for this difference remains contested. Here possible explanations were tested using a sample of couples where, because they had experienced a life event that was severe for both members, both the woman and man were at risk of depression. There was no evidence to suggest that the higher rage of depression among women in this sample was the result of a measurement artefact. In addition, men were not more likely to develop alternative, externalising, disorders to depression. If anything, women were more likely to experience and express anger about the life event. Consistent with an explanation based on gender differences in roles, women were only at greater risk of depression following an event involving children, housing and reproduction, and then only when there were clear gender differences in associated roles. Such a specific difference cannot be explained easily as a result of biological differences, particularly as among women rates of depression did not vary by parity. In conclusion it seems likely that women's greater risk of depression is a consequence of gender differences in roles, which lead to differences in the experience of life events.

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We present a study of the interaction of seven organophosphorous (OP) compounds with models of a silica surface using electronic structure calculations. Two of the OP species are chemical-warfare nerve agents (sarin and soman) and the rest are organophosphate (methyl dichlorophosphate, dimethyl chlorophosphate, and trimethyl phosphate) or organophosphonate (dimethyl methylphosphonate and diisopropyl methylphosphonate) mimics utilized in recent experiments. Calculations that approximate an amorphous silica surface by a simple gas-phase silanol molecule qualitatively reproduce the trend in binding energies determined in recent ultrahigh vacuum experiments. These calculations also show that, of the various atoms in the OP species that can accept hydrogen bonds from silanol groups, the oxygen atom that forms a double bond with the central phosphorus atom provides the largest binding energy, followed first by the remaining oxygen atoms and then by the halogen atoms. Quantitative comparisons with experiments are established by using calculations that more rigorously appoximate an amorphous silica surface with silica clusters that contain one or two silanol groups. MP2 calculations of the binding energies extrapolated to the complete-basis-set limit in a cluster model exhibiting a single isolated silanol group differ from the recent ultrahigh vacuum experimental values by less than 1 kcal/mol for many of the OP compounds examined. Calculations on a silica cluster with two silanol groups reveal the possibility of formation of two hydrogen bonds with the OP compounds and produce binding energies that are also consistent with other recent measurements. Symmetry-adapted perturbation theory is used to provide deeper insight into the origin of the exceptionally strong hydrogen bonds established between silica surfaces and OP compounds.

A fundamental understanding of the forces that drive uptake and binding of aromatic molecules on well-characterized surfaces such as silica is important for predicting the fate of toxic industrial compounds in the environment. Therefore, the adsorption of simple substituted benzene derivatives has been investigated on a hydroxyl-functionalized surface to probe the effects of electron withdrawing and donating functional groups on gas–surface binding. Specifically, this work probes how methyl and halide functional groups affect the properties of the OH---π hydrogen bond and other surface–adsorbate interactions that play an important role in the uptake of aromatic molecules. Our approach utilizes infrared spectroscopy to study hydrogen-bond formation and temperature-programmed desorption to measure activation energies of desorption. Results from this work indicate that substituted benzene derivatives adsorb to silica via a cooperative effect involving the SiOH---π hydrogen bond and additional substituent–surface interactions that result in unusually high desorption energies.

Background.Although rates of sustained virologic response (SVR) after hepatitis C virus (HCV) treatment with direct-acting antivirals (DAAs) surpass 90% in trials and some more “real world” settings, some patients, such as those with substance use disorders, will be challenged to adhere to HCV care.Methods.To assess the feasibility of 2 strategies for financially incentivizing adherence to HCV care, patients with a substance use history prescribed 12 weeks of a sofosbuvir-containing regimen were randomized to either fixed or lottery-based monetary incentives for attending clinic appointments, pill count adherence >90%, and SVR achievement. Electronic medication monitoring provided an objective measure of DAA adherence.Results.Fifty-nine participants were randomized to the lottery (n = 31) or fixed-incentive (n = 28) arms. All 31 (100%) in the lottery arm and 24 of 28 (86%) in the fixed arm completed 12 weeks of therapy. By intent-to-treat, 93% in the lottery arm and 92% in the fixed arm achieved SVR (estimated difference: 0.5%; 95% confidence interval, −17.5 to 18.8). Overall, 92% of scheduled visits were attended without significant differences between arms. The mean adherence ratio (days with ≥1 bottle opening:monitored days) was 0.91 for lottery and 0.92 for fixed arms.Conclusions.In this pilot, fixed- and lottery-based financial incentives were successfully implemented and accepted by patients with a substance use history. High levels of HCV therapy and care adherence, as well as rates of SVR, were observed. Financial incentives may be useful to support treatment adherence in patients with substance use disorders and should be tested in a larger, randomized, controlled trial.

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