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One-carbon (C1) substrates are attractive feedstocks for biological upgrading as part of a circular, carbon-negative bioeconomy. Nature has evolved a diverse set of C1-trophs that use a variety of pathways. Additionally, intensive effort has recently been invested in developing synthetic C1 assimilation pathways. This complicated landscape presents the question: “What pathways should be used to produce what products from what C1 substrates?” To guide the selection, we calculate and compare maximal theoretical yields for a range of bioproducts from different C1 feedstocks and pathways. The results highlight emerging opportunities to apply metabolic engineering to specific C1 pathways to improve pathway performance. Since the C1 landscape is dynamic, with new discoveries in the biochemistry of native pathways and new synthetic alternatives rapidly emerging, we present detailed procedures for these yield calculations to enable others to easily adapt them to additional scenarios as a foundation for establishing industrially relevant production strains. 

This study investigates the implementation of a classroom response system in STEM education in a higher education context. The study used ExplainIt, a web-based classroom response system designed to support students’ self-explanations and provide instant feedback. Data were collected from 32 undergraduate students using four instruments including demographic information, self-efficacy, engagement, and system evaluation. The results showed that students reported positive learning experiences, demonstrated increased self-efficacy in STEM content, and indicated high levels of engagement following their use of ExplainIt. 

The effects of abrasion on the heating performance of carbon nanotube (CNT)/epoxy composites were investigated in terms of Joule’s heat, convective heat, and radiative heat under moderate-to-severe and localized abrasive conditions. While the overall heating behavior was characterized by the heating rate and the curvature of the transient response, a numerical solution of the heat equation was used to quantify convective and radiative heat transfers, incorporating the specific heat of each component, the convective heat transfer coefficient, and the Biot number. CNT reinforcement significantly improved wear resistance at a CNT concentration of 0.31 vol. %, but the presence of micro-voids led to a slight increase in wear rate with additional CNT inclusion. Using an equivalent circuit model, local and severe abrasion scenarios were analyzed to determine the variation in electrical conductivity with temperature at different degrees of abrasion, indicating the impact of scattering effects. This analysis provides valuable insights for estimating both wear resistance and the heating performance of self-heated surface materials, with potential applications in future space technologies. 

A painting, like human skin, develops cracks on the surface as it dries and ages. The painting cracks, also known as craquelure, are often considered analogous to human fingerprints; these have been regarded as a unique signature reflective of the painting’s characteristics and are important in art authentication. Intriguingly, studies in other fields, such as geology, have observed the presence of distinctive characteristics in soil desiccation cracks. These cracks exhibit self-similarity, forming patterns that suggest broader geological processes at work. In light of this connection, the primary objective of this study is to investigate whether the painting cracks also exhibit a self-similar nature. By delving into this, we seek to shed light on the underlying properties of the painting cracks. This study also aims to investigate whether the characteristic self-similar trait of the cracks can serve as an identifier in relation to the provenances of the paintings. To this end, this study adopts the methodology originally designed to characterize the phenotypic traits of 3D particle geometries in granular materials research. This study develops a 2D equivalent concept, focusing on the phenotypic traits of the individual islands enclosed by cracks within paintings. The results successfully demonstrate that the phenotypic trait of painting cracks exhibits a self-similar nature, which can reveal characteristics associated with the provenances of paintings. The findings will offer valuable insights into the scientific examination of artworks based on painting cracks.