Alexithymia may explain the relationship between autistic traits and eating disorder psychopathology

Background: Autistic people are disproportionately vulnerable to anorexia nervosa and other eating disorders (ED), and within the general population, autistic traits correlate with ED psychopathology. A putative mechanism which may underpin this heightened risk is alexithymia, a difficulty identifying and describing emotional states which is observed in both autism and ED. In two experiments with independent non-clinical samples, we explored whether alexithymia might mediate the heightened risk of eating psychopathology in individuals high in autistic traits. Methods: Our first experiment used the PROCESS macro for SPSS to examine relationships between alexithymia (measured by the Toronto Alexithymia Scale (TAS-20)), autistic traits (autism quotient (AQ)), and eating psychopathology (Eating Attitudes Test (EAT-26)) in 121 participants. Our second experiment (n = 300) replicated and furthered this analysis by examining moderating effects of sex and controlling for anxiety and depression as covariates. We also included an additional performance-based measure of alexithymia, the Levels of Emotional Awareness Scale (LEAS). Results: Study 1 suggested that TAS-20 scores mediated the relationship between heightened autistic traits and eating psychopathology. Replication and further scrutiny of this finding, in study 2, revealed that this mediation effect was partial and specific to the female participants in this sample. The mediation effect appeared to be carried by the difficulty identifying feelings subscale of the TAS-20, even when depression and anxiety were controlled for. LEAS scores, however, were not significantly related to autistic traits or eating psychopathology. Limitations: Cross-sectional data prevents any conclusions around the direction and causality of relationships between alexithymia, autistic traits, and eating psychopathology (alongside depression and anxiety), necessitating longitudinal research. Our non-clinical sample was predominantly Caucasian undergraduate students, so it remains to be seen if these results would extrapolate to clinical and/or autistic samples. Divergence between the TAS-20 and LEAS raises crucial questions regarding the construct validity of these measures. Conclusions: Our findings with respect to autistic traits suggest that alexithymia could partially explain the prevalence of ED in autistic people and may as such be an important consideration in the pathogenesis and treatment of ED in autistic and non-autistic people alike. Further research with clinical samples is critical to explore these ideas. Differences between men and women, furthermore, emphasize the importance of looking for sexspecific as well as generic risk factors in autistic and non-autistic men and women

A Lattice-Boltzmann model for simulating bedform-induced hyporheic exchange

The Lattice-Boltzmann (LB) method is applied here for the first time to simulate bedform-induced hyporheic exchange flow in a reduced complexity model. The flexibility of the LB allows surface and hyporheic flows to be resolved together, in contrast to other approaches for similar model domains, in which surface flow is usually solved independently, and then the solution of the surface flow provides the boundary conditions to model the hyporheic exchange flow. At the same time, the superior computational efficiency of LB allows the use of Large Eddy Simulations within transient simulations. Numerical results show a faithful reproduction of pressure along the bedform surface—especially, the pressure drop leeward to the dune. Results also show short-time-dependent phenomena which were previously described only in the context of DNS studies over reduced-size computational domains. Short-time-dependent phenomena include pressure oscillations and time-dependence of hyporheic zone morphology, with the latter eventually extending beyond the limits of a single bedform element.</jats:p

Influence of DC electric field upon the production of oil-in-water-in-oil double emulsions in upwards mm-scale channels at low electric field strength

A novel approach to create O/W/O is developed and described to achieve uniform oil drop size coated with thin layers of water. Drops were created using a test cell where the DC field is applied between different internal diameter (ID) needles (from which the O/W emulsion emits upwards into a continuous oil phase) and a grounded metal ring which was located at selected distances from the needle top. The advantages compared to the previous techniques consist of possibility of control on drop size and coating layer of the water using low electric field. A high speed imaging technique has been applied to determine drop size under different flow and electric field conditions. Without the electric field, several flow regimes were observed; stable formation of both the O/W/O emulsion and the O/W emulsion upstream of the cell was possible over a range of Reynolds numbers from 80 to 100. The effect of the electric field was found to be reverse below electric field strength of 60&nbsp;kV&nbsp;m−1, beyond this critical value there was significant impact upon the flow regime, drop size and emulsion structure. The impact of the electric field strength upon flow pattern and emulsion structure and a quantitative analysis of droplet size are presented. The work shows the results for the controlled creation of complex emulsion droplets combining electric field and mm scale channels. The differences with the other physical processes reported in the literature are discussed