Feeding difficulties are not uncommon following surgery for the correction of congenital heart defects, especially in the neonate. The most important risk factors appear to be an increased RACHS score and prolonged postoperative intubation. Hopefully, by defining the risk factors, proactive management strategies can be developed to minimize these problems following neonatal congenital heart surgery.

Surfactants are ubiquitous constituents of commercial and biological systems that function based on complex structure-dependent interactions. Sophorolipid (SL) n-alkyl esters (SL-esters) comprise a group of modified naturally derived glycolipids from Candida bombicola. Herein, micellar self-assembly behavior as a function of SL-ester chain length was studied. Surface tensions as low as 31.2 mN/m and critical micelle concentrations (CMCs) as low as 1.1 μM were attained for diacetylated SL-decyl ester (dASL-DE) and SL-octyl ester, respectively. For deacetylated SL-esters, CMC values reach a lower limit at SL-ester chains above n-butyl (SL-BE, 1-3 μM). This behavior of SL-esters with increasing hydrophobic tail length is unlike other known surfactants. Diffusion-ordered spectroscopy (DOSY) and T relaxation NMR experiments indicate this behavior is due to a change in intramolecular interactions, which impedes the self-assembly of SL-esters with chain lengths above SL-BE. This hypothesis is supported by micellar thermodynamics where a disruption in trends occurs at n-alkyl ester chain lengths above those of SL-BE and SL-hexyl ester (SL-HE). Diacetylated (dA) SL-esters exhibit an even more unusual trend in that CMC increases from 1.75 to 815 μM for SL-ester chain lengths of dASL-BE and dASL-DE, respectively. Foaming studies, performed to reveal the macroscopic implications of SL-ester micellar behavior, show that the observed instability in foams formed using SL-esters are due to coalescence, which highlights the importance of understanding intermicellar interactions. This work reveals that SL-esters are an important new family of green high-performing surfactants with unique structure-property relationships that can be tuned to optimize micellar characteristics.

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Background Exposure to per- and polyfluoroalkyl substances (PFAS) is a public health issue globally. In Australia high concentrations of PFAS have been found in environments close to sites where Aqueous Film Forming Foams (AFFF) were historically used for firefighting activities. This has resulted in significant community concern about the potential long-term health effects of these chemicals. Objective We describe residents’ perceptions and experiences of PFAS in three regional Australian towns where exposure has occurred. Methods We conducted focus groups to generate free-flowing open discussion on PFAS in three affected communities, including some with significant numbers of First Nations Peoples. We recruited participants using a range of media outlets and postal services. Focus group transcripts were analysed thematically to identify major shared concerns using Atlas Ti. Results One hundred and eighty residents attended fifteen focus groups that were conducted in the three communities. They included 69 First Nations People living in three communities near the town of Katherine in the Northern Territory. Study participants were concerned about potential physical health effects of exposure to PFAS, such as cancer clusters, unexplained deaths, potential exacerbation of existing health conditions, and the future health of their children. They expressed feelings of stress and anxiety about living with uncertainty related to the possible health and the socio-economic impacts of PFAS contamination in their communities. Conclusion While research has concentrated on the physical health effects of PFAS, more attention needs to be given to the immediate psychosocial impacts of living in an affected community.

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