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Disorder is known to have a profound influence on classical phase transitions, and it is anticipated to be even more important for quantum phase transitions. However, experimental investigation of the influence of disorder on phase transitions normally requires numerous samples over the range of disorder. Here, we investigate the field-driven quantum phase transition in the antiferromagnet LiErF 4 . The isotopic distribution of natural Er permits us to probe the transition in the clean and dirty regimes in the same sample. 167 Er, with non-zero nuclear spin on 23% of the Er sites, induces random mass disorder in the dirty (low-temperature) regime. We use specific heat and ac magnetic susceptibility experiments to identify a crossover between the two regimes at T = 150 mK. The critical behavior is consistent with a violation of the Harris criterion in the clean regime and a change of universality class in the dirty regime., Competing Interests: Competing interests: The authors declare no competing interests., (© 2025. The Author(s).)

Objective: Children with amplified musculoskeletal pain (AMPS) experience significant functional disability, with impairment in their ability to participate in age-appropriate activities of daily living. Parental factors play an important role in a child's pain symptoms and treatment outcomes, with parental pain catastrophizing and protective behaviors linked to several maladaptive outcomes for children. Aims of the current study were to examine how parental pain catastrophizing, child pain catastrophizing, and parental protective behaviors longitudinally impacted functional disability for children with AMPS., Methods: Archival data were examined from parent-child dyads presenting to a tertiary pain clinic for treatment of AMPS. Over 1 year, parents completed measures assessing the level of pain catastrophizing, common behavioral responses to child pain, and child functional disability. Children completed measures of pain catastrophizing and functional disability. Measures were collected at initial evaluation, 6-months, and 12-months. Latent growth models (LGM) were conducted to examine how to study variables longitudinally impacted the rate of change in child functional disability., Results: Examining a comprehensive LGM of study variables, parental catastrophizing emerged as the sole contributing factor to slower improvement in functional disability., Conclusions: The strong influence of parental pain catastrophizing on functional disability may relate to parents limiting behaviors that promote adaptive coping in children with pain. As such, parents who catastrophize may benefit from specific interventions to increase their use of adaptive behavioral responses, such as redirecting children to complete functional activities and encouraging the use of positive coping skills for pain-related distress., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Society of Pediatric Psychology.)

Previous research has found that women at peak fertility show greater interest in extra-pair sex. However, recent replications have failed to detect this effect. In this study, we add to this ongoing debate by testing whether sociosexuality (the willingness to have sex in the absence of commitment) is higher in women who are at peak fertility. A sample of normally ovulating women ( N = 773) completed a measure of sociosexuality and had their current fertility status estimated using the backward counting method. Contrary to our hypothesis, current fertility was unrelated to sociosexual attitudes and desires, even when relationship status was included as a moderator. These findings raise further doubts about the association between fertility and desire for extra-pair sex.