Reversible exchange bias in epitaxial V2O3/Ni hybrid magnetic heterostructures.

In this work we present a temperature and angular dependent study of the structural and magnetic properties in highly crystalline V2O3/Ni/Zr magnetic heterostructure films. Our investigation focuses on the coupling between the ferromagnetic Ni layer and V2O3layer which undergoes an antiferromagnetic/paramagnetic phase transition coupled to the structural phase transition of the material at around 150 K. Structural investigations using x-ray diffraction reveal highly crystalline films of a quality which has previously not been reported in the literature. The Ni layers display an absence of in-plane magnetic anisotropy owing to the highly textured (1 1 1) layering of the Ni films on the underlying V2O3(0 0 0 1) oriented layer. During the transition we observe a strain related enhancement of the coercivity and the onset of a weak exchange bias for cooling under an external magnetic field. Heating the films to above the transition temperature, the exchange bias in the Ni is removed and can be reversed upon subsequent cooling under an inverted external magnetic field. Using temperature dependent polarized neutron reflectometry we investigate the film structure at the interface, capturing the magnetic and nuclear profiles.

Prevalence of Autism Spectrum Disorder in 7-9-Year-Old Children in Denmark, Finland, France and Iceland: A Population-Based Registries Approach Within the ASDEU Project.

We estimated autism spectrum disorder (ASD) prevalence in 7-9 year-old children in 2015 using data from three nationwide health registry systems (Denmark, Finland, Iceland) and two French population-based regional registries. Prevalence ranged from 0.48% in South-East France to 3.13% in Iceland (South-West France: 0.73%, Finland: 0.77%, Denmark: 1.26%). Male/female ratios ranged from 3.3 in Finland to 5.4 in South-West France. Between 12% (Denmark) and 39% (South-West France) of cases were diagnosed with intellectual disability. The variations in population-based ASD prevalence across four European countries with universal health care practices likely reflect variation in detection, referral and diagnosis practices and autism awareness across these areas. Using established population-based data systems is an efficient approach to monitor ASD prevalence trends over time.

Stress, depression, workplace and social supports and burnout in intellectual disability support staff.

BACKGROUND: Staff providing support to people with intellectual disabilities are exposed to stressful work environments which may put them at an increased risk of burnout. A small prior literature has examined predictors of burnout in disability support staff, but there is little consensus. In this study, we examined direct and indirect associations between work stressors (i.e. challenging client behaviour), staff emotional response to the behaviour (i.e. perceived stress, anxiety, depression), social and organisational support resources, and staff burnout. METHODS: A short survey examined client behaviour, staff psychological stress, anxiety, depression, social support (number, satisfaction), organisational support and burnout in 80 disability support staff in a community setting. RESULTS: Burnout levels were similar to or slightly lower than normed values for human services staff. Cross-sectional regression analyses indicated that depression symptoms and organisational support were related to worse emotional exhaustion and depersonalisation, whereas less social support was related to less personal accomplishment. Social support satisfaction (but not social support number or organisational support) moderated between high psychological stress to less emotional exhaustion. CONCLUSIONS: Taken together, these results suggest that depression symptoms and low organisational support were frequently concurrent with burnout symptoms. Furthermore, worker's personal and organisational supports may have helped bolster their sense of personal accomplishment, and buffered against the potential for emotional exhaustion.

Hemodynamic profile of stress-induced anticipation and recovery.

Systolic and diastolic blood pressure, heart rate, stroke volume, cardiac output, and total peripheral resistance were measured in 100 healthy men and women with the aim of investigating hemodynamic profile during anticipation of, and recovery from, exposure to active and passive laboratory stressors. A 5-min anticipatory period preceded two tasks, both of which lasted 2.5 min. The tasks were mental arithmetic ('beta-adrenergic' stress) and the cold pressor test ('alpha-adrenergic' stress). Each task was followed by a 5-min recovery period. Blood pressure and heart rate were measured with a FinaPres 2300e, and stroke volume, cardiac output, and total peripheral resistance were computed from these parameters. Salivary cortisol was measured in relation to both tasks, and participants completed tests of state and trait anxiety, locus of control, and hostility. As expected, mental arithmetic and the cold pressor test elicited myocardial and vascular patterns of reactivity, respectively. However, contrary to expectations, anticipatory and recovery hemodynamic profile involved essentially vascular responding for both stressors. Salivary cortisol increased in response to both tasks but only weakly correlated with hemodynamic changes. None of the subjective measurements was a strong predictor of physiological reactivity. The findings suggest that stress-induced anticipatory and recovery reactivity may be generally vascular rather than myocardial. This could have important implications in light of suggestions that anticipatory and recovery responses may be better predictors of subsequent cardiovascular disease than direct stress-induced reactivity.

Effects of video-relayed social support on hemodynamic reactivity and salivary cortisol during laboratory-based behavioral challenge.

The authors tested the effects of a laboratory analogue of social support on reactivity to laboratory-based behavioral challenge. Video-relayed supportive commentary was provided by a same-sex confederate while participants (40 healthy men and women assigned to support and no-support groups) performed a demanding computer task, and their heart rate, systolic and diastolic blood pressure, and salivary cortisol were measured. The authors found that heart rate and cortisol level (but not blood pressure) were attenuated in the support condition for both genders. Objective performance on the task was similar in both groups, but the social support group reported higher levels of perceived support and rated the task as easier than did participants in the no-support condition. Video presentation offers new opportunities for systematically examining social support and its effects.