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Actinium-based therapies could revolutionize cancer medicine but remain tantalizing due to the difficulties in studying and limited knowledge of Ac chemistry. Current efforts focus on small synthetic chelators, limiting radioisotope complexation and purification efficiencies. Here, we demonstrate a straightforward strategy to purify medically relevant radiometals, actinium(III) and yttrium(III), and probe their chemistry, using the recently discovered protein, lanmodulin. The stoichiometry, solution behavior, and formation constant of the 228 Ac 3+ -lanmodulin complex and its 90 Y 3+ / nat Y 3+ / nat La 3+ analogs were experimentally determined, representing the first actinium-protein and strongest actinide(III)-protein complex (sub-picomolar K d ) to be characterized. Lanmodulin’s unparalleled properties enable the facile purification recovery of radiometals, even in the presence of >10 +10 equivalents of competing ions and at ultratrace levels: down to 2 femtograms 90 Y 3+ and 40 attograms 228 Ac 3+ . The lanmodulin-based approach charts a new course to study elusive isotopes and develop versatile chelating platforms for medical radiometals, both for high-value separations and potential in vivo applications. 

Software applications in educational technology have been a strong driving force for the success of online learning at all levels. These applications are created for various purposes and are used by a range of experts. The development of a successful educational technology software takes a deliberate team effort and thoughtful project management. This interpretive case study details the processes, successes, and challenges determined throughout the development of an educational web application, the Social Performance Optimization Tool (SPOT). In describing the evolution of SPOT, and the processes the heterogeneous team followed in the development of the web application, this study provides analysis and guidance to educational researchers who are interested in developing educational web applications in the future. The study described how authors mindfully adopted software design models, team management techniques, and communication tools. Additionally, the paper highlights practical and unique implications developers must account for when working in higher education contexts. 

In adipose, insulin functions to suppress intracellular lipolysis and secretion of nonesterified fatty acid (NEFA) into plasma. We applied glucose and NEFA minimal models (MM) following a frequently sampled intravenous glucose tolerance test (FSIVGTT) to assess glucose-specific and NEFA-specific insulin resistance. We used total NEFA and individual fatty acids in the NEFA MM, comparing the model parameters in metabolic syndrome (MetSyn) subjects ( n = 52) with optimally healthy controls (OptHC; n = 14). Results are reported as mean difference (95% confidence interval). Using the glucose MM, MetSyn subjects had lower [−73% (−82, −57)] sensitivity to insulin (S i ) and higher [138% (44, 293)] acute insulin response to glucose (AIR g ). Using the NEFA MM, MetSyn subjects had lower [−24% (−35, −13)] percent suppression, higher [32% (15, 52)] threshold glucose (g s ), and a higher [81% (12, 192)] affinity constant altering NEFA secretion (ϕ). Comparing fatty acids, percent suppression was lower in myristic acid (MA) than in all other fatty acids, and the stearic acid (SA) response was so unique that it did not fit the NEFA MM. MA and SA percent of total were increased at 50 min after glucose injection, whereas oleic acid (OA) and palmitic acid (PA) were decreased ( P < 0.05). We conclude that the NEFA MM, as well as the response of individual NEFA fatty acids after a FSIVGTT, differ between OptHC and MetSyn subjects and that the NEFA MM parameters differ between individual fatty acids.