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There have been some interesting recent advances in understanding the notion of mechanical disorder in structural glasses and the statistical mechanics of these systems' low-energy excitations. Here we contribute to these advances by studying a minimal model for structural glasses' elasticity in which the degree of mechanical disorder-as characterized by recently introduced dimensionless quantifiers-is readily tunable over a very large range. We comprehensively investigate a number of scaling laws observed for various macro, meso and microscopic elastic properties, and rationalize them using scaling arguments. Interestingly, we demonstrate that the model features the universal quartic glassy vibrational density of states as seen in many atomistic and molecular models of structural glasses formed by cooling a melt. The emergence of this universal glassy spectrum highlights the role of self-organization (toward mechanical equilibrium) in its formation, and elucidates why models featuring structural frustration alone do not feature the same universal glassy spectrum. Finally, we discuss relations to existing work in the context of strain stiffening of elastic networks and of low-energy excitations in structural glasses, in addition to future research directions.

Objective: Attention is a core process underlying competence in higher-order cognitive abilities. Previous research suggests that healthy children from low socioeconomic status (SES) backgrounds perform poorly, relative to those from higher SES backgrounds, on tasks assessing attentional abilities. In this pilot study, we investigated the effects of an attention-training intervention on task performance in low-SES children., Method: We conducted a quasi-controlled trial with stratified randomisation, using a pre-test/ post-test design. Participants were low-SES children aged 7-13 years. Each was assigned to either an intervention group, a play control group, or a test-only control group (n = 5 per group). We implemented a ten-week manualised cognitive rehabilitation program, Pay Attention!, administering standardised tests of attention, working memory, and inhibition before and after the intervention. Between- and within-group analyses and Reliable Change Index statistics evaluated differences in scores from pre- to post-intervention., Results: Analyses detected no notable between-group differences at either pre- or post-intervention testing. However, on tests of selective attention, attentional control, and inhibition, there were significant within-group and positive individual reliable changes exclusive to the intervention-group participants., Conclusions: Given the variability in our findings, more research needs be conducted with a larger sample to determine, with greater rigour, the efficacy of the intervention within samples of healthy children from low-SES backgrounds.