Daily parent-adolescent cortisol associations: Unpacking the direction of effects

Prior studies suggest bidirectional relationships between parent and adolescent behavior. This study examined how parents and their adolescent child's cortisol patterns are associated across days and if there are bidirectional associations between parent and child cortisol. Participants included two samples of employees and their children who participated in a daily diary study where diurnal salivary cortisol was collected on four study days (N = 318 dyads, M youth age = 13.18 years, 52 % female). Autoregressive cross-lagged models were used to estimate parent-driven effects (parent cortisol effects on adolescent cortisol) and adolescent-driven effects (adolescent cortisol effects on parent cortisol). Adolescents’ steeper cortisol awakening response (CAR) was significantly associated with parents’ steeper CAR the following day. Adolescents’ higher bedtime cortisol levels were also significantly associated with parents’ higher bedtime cortisol levels the following day. Parents’ cortisol did not predict their children's next-day cortisol. Results support a primarily adolescent-driven process of stress transmission in families. These results suggest that interventions to reduce adolescent stress, as well as to reduce parents’ reactivity to adolescents, may be warranted

Adolescent effects on mothers' bedtime cortisol: Cognitive interference as a mediating mechanism

Prior studies have shown that parent and adolescent cortisol are associated across days and that this covariation may be adolescent-driven. This study extends this literature by (a) testing whether parents' cognitive interference (i.e., distracting and ruminative thoughts potentially due to worry) mediates the linkages between adolescent and next-day parent cortisol and (b) whether these linkages were moderated by parent gender or warmth. Daily diary data, including bedtime cortisol, were collected on two samples of employees and their adolescent-aged children (N = 318 dyads, Myouth age = 13.18 years, 74% mothers). We tested mediation with autoregressive cross-lagged models. Moderated mediation by parent gender was found in our bedtime cortisol models. Higher adolescent bedtime cortisol levels were associated with higher next-day levels of mothers' cognitive interference. In turn, higher levels of mothers' cognitive interference were linked to higher mothers' same-day bedtime cortisol levels. These linkages were not significant for fathers. Cognitive interference did not mediate the associations between child and parent area under the curve or cortisol awakening response. No moderation was evident for parental warmth. Results suggest that mothers' cognitions play a key role in the transmission of elevated bedtime cortisol levels from adolescents to their mothers

Density functional theory based screening of ternary alkali-transition metal borohydrides: A computational material design project

The dissociation of molecules, even the most simple hydrogen molecule, cannot be described accurately within density functional theory because none of the currently available functionals accounts for strong on-site correlation. This problem led to a discussion of properties that the local Kohn-Sham potential has to satisfy in order to correctly describe strongly correlated systems. We derive an analytic expression for the nontrivial form of the Kohn-Sham potential in between the two fragments for the dissociation of a single bond. We show that the numerical calculations for a one-dimensional two-electron model system indeed approach and reach this limit. It is shown that the functional form of the potential is universal, i.e., independent of the details of the two fragments.We acknowledge funding by the Spanish MEC (Grant No. FIS2007-65702-C02-01), “Grupos Consolidados UPV/EHU del Gobierno Vasco” (Grant No. IT-319-07), and the European Community through e-I3 ETSF project (Grant Agreement No. 211956).Peer reviewe

On the mechanisms governing gas penetration into a tokamak plasma during a massive gas injection

A new 1D radial fluid code, IMAGINE, is used to simulate the penetration of gas into a tokamak plasma during a massive gas injection (MGI). The main result is that the gas is in general strongly braked as it reaches the plasma, due to mechanisms related to charge exchange and (to a smaller extent) recombination. As a result, only a fraction of the gas penetrates into the plasma. Also, a shock wave is created in the gas which propagates away from the plasma, braking and compressing the incoming gas. Simulation results are quantitatively consistent, at least in terms of orders of magnitude, with experimental data for a D 2 MGI into a JET Ohmic plasma. Simulations of MGI into the background plasma surrounding a runaway electron beam show that if the background electron density is too high, the gas may not penetrate, suggesting a possible explanation for the recent results of Reux et al in JET (2015 Nucl. Fusion 55 093013)

Velocity-space sensitivity of the time-of-flight neutron spectrometer at JET

The velocity-space sensitivities of fast-ion diagnostics are often described by so-called weight functions. Recently, we formulated weight functions showing the velocity-space sensitivity of the often dominant beam-target part of neutron energy spectra. These weight functions for neutron emission spectrometry (NES) are independent of the particular NES diagnostic. Here we apply these NES weight functions to the time-of-flight spectrometer TOFOR at JET. By taking the instrumental response function of TOFOR into account, we calculate time-of-flight NES weight functions that enable us to directly determine the velocity-space sensitivity of a given part of a measured time-of-flight spectrum from TOFOR

Relationship of edge localized mode burst times with divertor flux loop signal phase in JET

A phase relationship is identified between sequential edge localized modes (ELMs) occurrence times in a set of H-mode tokamak plasmas to the voltage measured in full flux azimuthal loops in the divertor region. We focus on plasmas in the Joint European Torus where a steady H-mode is sustained over several seconds, during which ELMs are observed in the Be II emission at the divertor. The ELMs analysed arise from intrinsic ELMing, in that there is no deliberate intent to control the ELMing process by external means. We use ELM timings derived from the Be II signal to perform direct time domain analysis of the full flux loop VLD2 and VLD3 signals, which provide a high cadence global measurement proportional to the voltage induced by changes in poloidal magnetic flux. Specifically, we examine how the time interval between pairs of successive ELMs is linked to the time-evolving phase of the full flux loop signals. Each ELM produces a clear early pulse in the full flux loop signals, whose peak time is used to condition our analysis. The arrival time of the following ELM, relative to this pulse, is found to fall into one of two categories: (i) prompt ELMs, which are directly paced by the initial response seen in the flux loop signals; and (ii) all other ELMs, which occur after the initial response of the full flux loop signals has decayed in amplitude. The times at which ELMs in category (ii) occur, relative to the first ELM of the pair, are clustered at times when the instantaneous phase of the full flux loop signal is close to its value at the time of the first ELM