Tensile properties of freeze-cast collagen scaffolds: How processing conditions affect structure and performance in the dry and fully hydrated states.

Tensile properties of directionally freeze-cast biopolymer scaffolds are rarely reported, even though they are of interest from a fundamental science perspective and critical in applications such as scaffolds for the regeneration of nerves or when used as ureteral stents. The focus of this study is on collagen scaffolds freeze-cast with two different applied cooling rates (10 °C/min and 1 °C/min) in two freezing directions (longitudinal and radial). Reported are the results of a systematic structural characterization of dry scaffolds by scanning electron microscopy and the mechanical characterization in tension of both dry and fully hydrated scaffolds. Systematic structure-property-processing correlations are obtained for a comparison of the tensile performance of longitudinally and radially freeze-cast collagen scaffolds with their performance in compression. Collated, the correlations, obtained both in tension in this study and in compression for collagen and chitosan in two earlier reports, not only enable the custom-design of freeze-cast biopolymer scaffolds for biomedical applications but also provide new insights into similarities and differences of scaffold and cell-wall structure formation during the directional solidification of "smooth" and "fibrillar" biopolymers.

The Need for Community-Responsive and Flexible Sex Ed for Historically Marginalized Youth.

Introduction: When it is offered, sexuality education in the USA is far from standardized. While studies have explored differences in delivery and type of sexuality education across the USA, sexual and reproductive health inequities persist among historically marginalized groups (Latino/a/x, Black, African American, LGBTQ +). There is a critical need to better understand the systemic barriers to receiving effective sexuality education in these communities. Methods: Participatory research methods were used in working with a community advisory board (CAB)-consisting of emerging adults and service providers from community-based organizations (CBOs) serving youth-to examine how structural barriers contribute to adolescent sexual and reproductive health (ASRH) inequities in Massachusetts. CAB meetings and semi-structured interviews were conducted in the cities of Springfield (n = 14) and Lynn (n = 9) between December 2020 and May 2021. Results: Inflexible funding guidelines, a related evidence-based curricular mandate, and a lack of community-responsive sexuality education fail to meet the sexual and reproductive health (SRH) needs of these youth. Conclusions: Current evidence-based mandates must be revisited to improve young people's access to quality sexuality information in public schools. To guarantee sexuality education curricula is centered in the context of the community and population in which it is implemented, collaboration between youth-serving CBOs and school districts could improve students' overall experience and social-emotional growth by providing comprehensive, positive, and community-responsive curricula. Policy Implications: Funders and programming should prioritize community responsiveness by financially supporting and developing and/or adapting evidence-based curricula to better match the community's needs, which can be completed through culture-centered training and community-based partnership.

Design, Manufacture, and In vivo Testing of a Tissue Scaffold for Permanent Female Sterilization by Tubal Occlusion.

Current FDA-approved permanent female sterilization procedures are invasive and/or require the implantation of non-biodegradable materials. These techniques pose risks and complications, such as device migration, fracture, and tubal perforation. We propose a safe, non-invasive biodegradable tissue scaffold to effectively occlude the Fallopian tubes within 30 days of implantation. Specifically, the Fallopian tubes are mechanically de-epithelialized, and a tissue scaffold is placed into each tube. It is anticipated that this procedure can be performed in less than 30 minutes by an experienced obstetrics and gynaecology practitioner. Advantages of this method include the use of a fully bio-resorbable polymer, low costs, lower risks, and the lack of general anaesthesia. The scaffold devices are freeze-cast allowing for the custom-design of structural, mechanical, and chemical cues through material composition, processing parameters, and functionalization. The performance of the biomaterial and de-epithelialization procedure was tested in an in vivo rat uterine horn model. The scaffold response and tissue-biomaterial interactions were characterized microscopically post-implantation. Overall, the study resulted in the successful fabrication of resilient, easy-to-handle devices with an anisotropic scaffold architecture that encouraged rapid bio-integration through notable angiogenesis, cell infiltration, and native collagen deposition. Successful tubal occlusion was demonstrated at 30 days, revealing the great promise of a sterilization biomaterial.