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Davidson and co-authors recently published a study wherein they develop a superhydrophobic Janus membrane by coating one side of a polyester mesh with ZnO tetrapods. They use the membrane to create a multi-layered menstrual hygiene prototype that effectively wicks fluids.

Contextualized chemistry curricula have been shown to positively impact academic outcomes, especially in middle and secondary school levels. However, only a limited number of investigations on the impact of real-world contextualized curricula on students’ learning outcomes in chemistry lecture courses in postsecondary education have been reported. In this study, we investigated the effect of a contextualized chemistry curriculum on General Chemistry I students’ achievement scores and perceived relevance of chemistry content, as well as the correlation between students’ perceived content relevance and the achievement scores in the course. A treatment group was exposed to chemistry content enriched with real-world contexts, contextualized quizzes, and application cards activities, whereas a comparison group was taught through the conventional approach. Data included scores from a final chemistry test and a 5-point Likert scaled chemistry relevance survey. The survey generated three constructs, namely personal relevance, chemistry utility, and societal relevance. Results indicated significantly higher achievement scores for the treatment group compared to the comparison group, after controlling for ACT math scores, with a medium effect size (η2= 0.075). The treatment group also showed significantly higher mean rating scores on the three constructs compared to the comparison group (p< 0.05). Additionally, paired sample t-test results showed improved perceptions scores on the constructs in the Post survey for the treatment group, but a drop on the perceptions scores on the constructs, except Personal relevance for the comparison group. Additionally, Pearson correlation coefficients showed positive correlations between the constructs and the achievement scores, with significant linear relationships between the variables noted for the treatment group (p<.05). A significant correlation was only between Chemistry utility and performance for the comparison group. The results imply the potential of the context-based learning approaches reported herein to bolster performance and enhance chemistry relevance.

Nanobiomaterials are introducing new capabilities to coordinate cell selection, growth, morphology, and differentiation. Herein, we report that tuning the geometry of ordered arrays of nanopillars (NP) elicits specialized morphologies in adherent cells. Systematic analysis of the effects of the NP radius, height, and spacing reveals that stem cells assume either flattened, polarized, or stellate morphologies in direct response to interpillar spacing. Notably, on NPs of pitch near a critical spacing (dcrit≈ 2 μm for C3H10T1/2 cells), cells exhibit rounding of the cell body, pronounced polarization, and extension of narrow axon-like cell projections aligned with the square lattice of the NP array and extending hundreds of micrometers. Furthermore, increasing the NPs' aspect ratio from 12:1 to 50:1 to produce NPs with a corresponding reduction in the NP bending stiffness of 2 orders of magnitude amplified the cellular response and resulted in a previously unseen degree of cell polarization and alignment. The rapid morphological transformation is reproducible on surfaces that maintain key parameters of the NP geometry and spacing, is influenced by the cell seeding density, and persists for different stem cell lines and primary mesenchymal stem cells. The demonstrated ability to support various morphogenetic trends in stem cells by simply tuning the geometry of the NP substrates provides a stepping-stone for the future design of scaffolds where cellular morphology and alignment are crucial.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.