We extend the “Brownian bees” model of Berestycki et al. (2021, 2022) to cooperative reproduction, kA→(k+1)A, of a population of N symmetric random walkers with removal, at each birth event, of the particle farthest from the origin. Working in the limit N → ∞, we formulate a hydrodynamic free-boundary problem for this model. Using this formalism, we determine steady state population densities for all k and prove their linear stability for k ≤ 2 and instability for k ≥ 4. In the marginal case k=3, there is a whole continuous family of steady states at a single critical ratio of the reproduction and diffusion rates. Above criticality the population undergoes an asymptotically self-similar finite-time collapse to the origin. Below the criticality the population spreads diffusively, but the reproduction remains quantitatively relevant. For k ≥ 4, the unstable steady state separates regimes of a finite-time collapse and diffusive spreading. Here the collapse dynamics is asymptotically self-similar, and the population density exhibits a scale separation requiring a matched-asymptotic description. Our analytical predictions are confirmed by numerical solutions of the hydrodynamic free-boundary problem and by Monte Carlo simulations of the original microscopic model.
Backgrounds Individuals with developmental coordination disorder (DCD) attending higher-education institutions face challenges in their everyday life. Nevertheless, research regarding participation and quality of life (QoL) in this population is limited. Aim To explore determinants of participation and QoL in university students with probable DCD (pDCD) through structural equation modelling (SEM). Methods A cross-sectional comparative and correlational design. A random sample of 297 undergraduate university students was divided into three groups based on cutoff scores of the Adolescents & Adults Coordination Questionnaire: pDCD; n = 40, borderline pDCD (BpDCD) n = 45 and typically developing (TD) n = 212. Measures included self-report questionnaires relating to pDCD, attention deficit and hyperactivity disorder (ADHD) symptoms, executive functions (EF), including metacognition and behavioral regulation, as well as participation and QoL. Results Students with pDCD reported reduced participation and QoL and impairment in EF and ADHD compared to TD students. SEM results showed that pDCD had a direct significant effect on EF, ADHD symptoms and participation and an indirect effect on QoL, mediated most strongly by participation. ADHD and behavioral regulation had a direct effect on QoL, whereas the relationship between metacognition and QoL was mediated by participation. Conclusions and relevance Through a SEM model, this study demonstrated that pDCD in university students is associated with reduced participation and QoL, and emphasized the role of EF, ADHD and participation in explaining QoL. These findings offer important insights for the assessment and intervention of higher-education students with pDCD.
The broad autism phenotype (BAP), a continuum of subclinical autism-related traits, has been linked to cognitive control (CC) difficulties and to poorer everyday participation. These constructs have rarely been examined together, and whether the BAP-CC association depends on how CC is assessed remains unclear. This cross-sectional study examined how self-reported and task-based CC relate to BAP traits in non-clinical young adults, and how CC and BAP traits jointly relate to distinct facets of everyday participation. A non-clinical community sample (N = 177; ages 18–40) completed the Broad Autism Phenotype Questionnaire (BAPQ), the Adult Executive Functioning Inventory (ADEXI), a battery of CC tasks (ACE Explorer), and the Young Adults' Daily Participation Scale (YADAPS). FDR-corrected correlations and a path model with bootstrapped indirect effects examined how CC and BAP traits jointly account for variance in participation outcomes. Self-reported CC difficulties were substantially associated with BAP traits (ADEXI Total with BAPQ Total, r = .54, p < .001), whereas task-based CC showed little association. Participation performance was independently associated with both self-reported CC and BAP traits, which together accounted for a quarter of its variance. BAP traits were the only consistent correlate of the pleasure facets, whereas self-reported CC showed no association with either pleasure outcome and task-based CC showed weak and inconsistent associations. Subclinical autism-related variation is tied to self-reported rather than task-based CC, and the performance and pleasure facets of participation have distinct correlates. These findings position the BAP as a meaningful dimension of daily functioning beyond diagnostic thresholds.
The present checklist provides, for each species of the Red Sea, records from the Gulf of Suez, Gulf of Aqaba, and the Red Sea main basin together with its general distribution, English vernacular name and IUCN Red List status. This updated checklist enumerates 1,250 species, representing 165 families. Of these, 813 species are recorded from the Gulf of Aqaba and 350 from the Gulf of Suez. The list includes 65 species newly described to science since the last checklist of 2018. The most speciose families of Osteichthyes are Gobiidae (154 species), Labridae (85), Apogonidae (60), Blenniidae (41), Muraenidae (40), Carangidae (39), Pomacentridae (35), Lutjanidae (34), Syngnathidae (33), Epinephelidae (27), and Scorpaenidae (25). Among the Chondrichthyes, the most speciose families are Carcharhinidae (17 species) and Dasyatidae (11). The total number of endemic species in the Red Sea is 177 species, of which, 36 species are endemic to the Gulf of Aqaba and 12 to the Gulf of Suez.
In recent years, there has been growing recognition of the importance of affirmative interventions for neurodiverse individuals. However, empirical evidence regarding such interventions in ADHD remains limited, particularly within conservative-religious cultures. The present study examined the effectiveness of a culturally sensitive, online psychosocial intervention for parents and children. The intervention is grounded in a salutogenic existential approach (SEA), an integrative framework that conceptualizes ADHD as a tension between a tendency toward freedom and reality demands (necessity), and aims to enhance sense of coherence (SOC), autonomous motivation, and support for neurodivergent identity while integrating the medical model with the neurodiversity framework. The study included 427 participants from the Ultra-Orthodox Jewish (UOJ) community in Israel: 311 in the intervention group and 116 in the control group. The intervention group participated in a 12-session online program that combined weekly lectures and practice for parents, along with audio story episodes and a workbook for children. Assessments were conducted before and after the intervention or waiting period using parent-report questionnaires: ADHD symptoms and comorbid difficulties (VADPRS), child functioning (WFIRS-P), and parental self-efficacy (TOPSE). The intervention group demonstrated a significant reduction in ADHD symptoms, behavioral problems, and anxiety/depression, as well as significant improvements in child functioning and parental self-efficacy. In the control group, only a minimal reduction in ADHD symptoms was observed, with no changes in the other domains. Between-group differences remained significant after controlling for background variables. The findings indicate the potential of an SEA-based intervention to improve parent and child functioning among individuals with ADHD symptoms in the UOJ community, and highlight the contribution of SEA as an integrative model for addressing ADHD.
