Empowering Pacific Patients on the Weight Loss Surgery Pathway: A Co-designed Evaluation Study.

PURPOSE: Despite having the highest medical needs by population for weight loss treatment, Pacific patients in Aotearoa New Zealand face substantial levels of attrition in publicly funded weight loss surgery programs. In collaboration with the Auckland City Hospital bariatric surgery team, a Pacific-led preoperative weight loss surgery program was co-designed, delivered, and evaluated between 2020 and 2023. MATERIALS AND METHODS: This was a single-arm, prospective co-designed evaluation study that took place at Auckland City Hospital in Aotearoa New Zealand. Participants were Pacific patients (n = 14) referred to the weight loss surgery program. Survey and video diaries were analyzed to determine if the program had the potential to increase Pacific patient retention through the preoperative stage of weight loss surgery, increase surgery completion rates, and improve the quality of treatment experiences. RESULTS: Nine out of 14 participants attended all preoperative sessions. Six participants subsequently underwent weight loss surgery. Program components that had positive impacts on patient success and satisfaction were accessibility, information quality, having Pacific role models, cultural safety, and the group support system. The patients found the program to be culturally anchored and there was support for the implementation of the program going forward. CONCLUSION: This study demonstrated how a culturally anchored intervention can increase patient retention for those patients who may not respond to mainstream treatment. Adjusting existing preoperative weight loss surgery programs to integrate Pacific-led models of healthcare has the potential to increase Pacific patient resiliency to follow through with surgery.

Subnanosecond geminate charge recombination in polymer-polymer photovoltaic devices.

We present direct spectroscopic evidence for substantial subnanosecond charge recombination in polymer-polymer blend photovoltaic devices. Early dynamics are dominated by exciton-charge interactions associated with high initial excitation densities. Independent of density, 30% of charges subsequently recombine geminately within just 2 nanoseconds, in contrast with fullerene blends. The remainder recombines with a half-life of approximately 200 ns. The morphological invariance of subnanosecond recombination suggests that its origin is inherent in the molecular structure at the polymer-polymer interface.

Low-temperature control of nanoscale morphology for high performance polymer photovoltaics.

Understanding and controlling nanoscale morphology is crucial to the performance of polymer bulk heterojunction solar cells, as well as other optoelectronic devices such as polymer light-emitting diodes, field-effect transistors, and sensors. In photovoltaic devices, optimum blend morphologies must be commensurate with the nanometer length scales of exciton diffusion and charge separation. We report on a generally applicable method of optimizing the phase segregation in polymer-polymer bulk heterojunctions based on tuning mixtures of low and high boiling point solvents. We have characterized the resulting blend morphologies with nanometer resolution using a transient absorption technique that probes the distribution of paths traveled by the excitons themselves prior to generating charges at an interface. Photovoltaic efficiencies are accounted for in terms of exciton diffusion, geminate pair separation, and polymer ordering, all of which are sensitive to the nanoscale morphology determined by the composition of the solvent mixture.