Abstract Mitoribosome biogenesis is an expensive metabolic process that is essential to maintain cellular respiratory capacity and requires the stoichiometric accumulation of rRNAs and proteins encoded in two distinct genomes. In yeast, the ribosomal protein Var1, alias uS3m, is mitochondrion-encoded. uS3m is a protein universally present in all ribosomes, where it forms part of the small subunit (SSU) mRNA entry channel and plays a pivotal role in ribosome loading onto the mRNA. However, despite its critical functional role, very little is known concerning VAR1 gene expression. Here, we demonstrate that the protein Sov1 is an in bona fide VAR1 mRNA translational activator and additionally interacts with newly synthesized Var1 polypeptide. Moreover, we show that Sov1 assists the late steps of mtSSU biogenesis involving the incorporation of Var1, an event necessary for uS14 and mS46 assembly. Notably, we have uncovered a translational regulatory mechanism by which Sov1 fine-tunes Var1 synthesis with its assembly into the mitoribosome.

Homophily, the tendency for individuals to preferentially interact with others similar to themselves is typically documented via self-report and, for children, adult report. Few studies have investigated homophily directly using objective measures of social movement. We quantified homophily in children with developmental disabilities (DD) and typical development (TD) using objective measures of position/orientation in preschool inclusion classrooms, designed to promote interaction between these groups of children. Objective measurements were collected using ultra-wideband radio-frequency tracking to determine social approach and social contact, measures of social movement and interaction. Observations of 77 preschoolers (47 with DD, and 30 TD) were conducted in eight inclusion classrooms on a total of 26 days. We compared DD and TD groups with respect to how children approached and shared time in social contact with peers using mixed-effects models. Children in concordant dyads (DD-DD and TD-TD) both moved toward each other at higher velocities and spent greater time in social contact than discordant dyads (DD-TD), evidencing homophily. DD-DD dyads spent less time in social contact than TD-TD dyads but were comparable to TD-TD dyads in their social approach velocities. Children’s preference for similar peers appears to be a pervasive feature of their naturalistic interactions.

Difficulty with attention is an important symptom in many conditions in psychiatry, including neurodiverse conditions such as autism. There is a need to better understand the neurobiological correlates of attention and leverage these findings for individuals in healthcare settings. Nevertheless, it remains unclear if it is possible to build robust dimensional predictive models of attention in neurodiverse populations. Here, we use five datasets to identify and validate functional connectome-based markers of attention. In dataset one, we use connectome-based predictive modelling and observe successful prediction of performance on an in-scan sustained attention task in a neurodiverse sample of youth. The predictions are not driven by confounds, such as head motion. In dataset two, we find the attention network model defined in dataset one generalizes to predict in-scan attention in a separate sample of neurotypical participants performing the same attention task. In datasets three to five, we use connectome-based identification and longitudinal scans to probe the stability of the attention network across months to years in individual participants. Our results help elucidate the brain correlates of attention in neurodiverse youth and support the further development of predictive dimensional models of other clinically-relevant phenotypes.

The individual effects of physical activity (PA) and sedentary behavior (SB) on health are well-recognized. However, little is known about the extent to which different combinations of these behaviors are associated with body composition and fall risk in older adults. This cross-sectional study examined the associations of mutually exclusive categories of PA and SB with body composition and fall risk in older women. Accelerometer-measured PA, body composition and fall risk (static and dynamic balance) parameters were assessed among 94 community-dwelling older women. The participants were categorized into four groups: active-low sedentary, active-high sedentary, inactive-low sedentary and inactive-high sedentary (active: ≥150 min/week moderate-to-vigorous PA (MVPA); low sedentary: lowest tertile of SB and light PA ratio). Compared to the inactive-high sedentary group, more favorable body composition and dynamic balance results were found in the active-low sedentary (body fat mass index (BFMI): β = −4.37, p = 0.002; skeletal muscle mass index (SMI): β = 1.23, p = 0.017; appendicular lean mass index (ALMI): β = 1.89, p = 0.003; appendicular fat mass index (AFMI): β = −2.19, p = 0.003; sit-to-stand: β = 4.52, p = 0.014) and inactive-low sedentary (BFMI: β = −3.14, p = 0.007; SMI: β = 1.05, p = 0.014; AFMI: β = −1.74, p = 0.005, sit-to-stand: β = 3.28, p = 0.034) groups. Our results suggest that PA programs focusing on concurrently achieving sufficient MVPA and reduced SB might promote a healthy body composition and reduced fall risk among older adults.

Background. Atypicalities in social approach are thought to be characteristic of children with autism spectrum disorder (ASD), but few studies have quantified the social movement of children with ASD using objective measures. The purpose of this paper is to introduce a new method—computational modeling of radio frequency identification (RFID) child tracking—for studying children with ASD in a naturalistic setting. We present the use of RFID measurements to investigate the velocity and social approach of children with ASD and typically developing (TD) children interacting together in preschool inclusion classrooms during repeated multi-hour observations. Methods. Observations of 14 preschoolers with ASD and 16 TD preschoolers in two inclusion classrooms on a total of 10 days yielded approximately 10 hours of data per child. Objective measurements of position and orientation were collected using four corner-mounted Ubisense ultra-wide sensors, which tracked a right and left tag worn by each child (in a vest) and teacher in the classroom. We calculate angular velocity, velocity, and social approach, and compare ASD and TD children on these parameters using multilevel statistical models. Results. In this initial exploration of the ASD phenotype in situ, children with ASD did not differ from TD children in angular velocity or velocity of movement in the classroom. Rather, pairs of TD children moved toward and away from each other at higher velocities than both pairs of children with ASD and pairs in which one child had ASD and the other child was TD. Children with ASD, however, moved toward and away from teachers at higher velocities than TD children. Limitations. Illustrative data from repeated observations of 30 children in two classrooms are reported. Results are preliminary. Conclusions. Multi-hour, objective measurements in a preschool inclusion classroom indicated that children with ASD did not move through space or turn at higher velocities than other children. Instead, ASD differences were evident in social approach. Children with ASD were slower in approaching peers but quicker in approaching teachers than were TD children. The results suggest the potential of modeling RFID measurements to produce a quantitative understanding of the ASD phenotype in naturalistic social contexts.