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Students’ beliefs about their abilities (called “lay theories”) affect their motivations, behaviors, and academic success. Lay theories include beliefs about the potential to improve intelligence (mindset), who (i.e., everyone or only some people) has the potential to be excellent in a field (universality), and whether reaching excellence in a field requires raw intellectual talent (brilliance). Research demonstrates that each of these beliefs influences students’ educational experiences and academic outcomes. However, it remains unclear whether they represent distinct latent constructs or are susceptible to the “jangle fallacy” (i.e., different names given to the same underlying construct). We conducted a multiphase, mixed-methods study to 1) evaluate whether mindset, universality, and brilliance beliefs represent conceptually and empirically discriminable concepts, and 2) evaluate whether mindset, universality, and brilliance beliefs contribute unique explanatory value for both psychosocial (e.g., sense of belonging) and academic outcomes (e.g., course grades). To address these questions, we developed and collected validity evidence for a new measure of science and math undergraduates’ lay theories, called the Undergraduate Lay Theories of Abilities (ULTrA) survey. Factor analyses suggest that mindset, brilliance, and universality are distinct and empirically discriminable constructs. Structural Equation Models indicate that each lay theory contributes unique predictive value to relevant outcomes. 

A roadmap of the spine During spinal cord surgery, intraoperative neuromonitoring (IONM) is used to reduce the risk of damage. Electrodes on muscles or scalp record the response to large-amplitude electrical stimuli delivered to the spinal cord. However, this method does not allow precise spatiotemporal characterization of spinal cord neurophysiology. Now, Russman et al. developed a microelectrode array that can be placed on the spinal cord during surgery and record with high spatiotemporal definition and high sensitivity the electrophysiological response to low-current stimulation, providing precise maps of spinal cord electrophysiology. These maps can be used during surgery to improve IONM. 

Abstract Interactive microbial communities are ubiquitous, influencing biogeochemical cycles and host health. One widespread interaction is nutrient exchange, or cross-feeding, wherein metabolites are transferred between microbes. Some cross-fed metabolites, such as vitamins, amino acids, and ammonium (NH4+), are communally valuable and impose a cost on the producer. The mechanisms that enforce cross-feeding of communally valuable metabolites are not fully understood. Previously we engineered a cross-feeding coculture between N2-fixing Rhodopseudomonas palustris and fermentative Escherichia coli. Engineered R. palustris excretes essential nitrogen as NH4+ to E. coli, while E. coli excretes essential carbon as fermentation products to R. palustris. Here, we sought to determine whether a reciprocal cross-feeding relationship would evolve spontaneously in cocultures with wild-type R. palustris, which is not known to excrete NH4+. Indeed, we observed the emergence of NH4+ cross-feeding, but driven by adaptation of E. coli alone. A missense mutation in E. coli NtrC, a regulator of nitrogen scavenging, resulted in constitutive activation of an NH4+ transporter. This activity likely allowed E. coli to subsist on the small amount of leaked NH4+ and better reciprocate through elevated excretion of fermentation products from a larger E. coli population. Our results indicate that enhanced nutrient uptake by recipients, rather than increased excretion by producers, is an underappreciated yet possibly prevalent mechanism by which cross-feeding can emerge. 

A new caridean shrimp, Alvinocaris costaricensis, is described from methane seeps in the eastern Pacific off Costa Rica. The new species is the 16th described species of the genus, and by molecular analysis appears closest to Alvinocaris komaii from the Lau Basin, southwestern Pacific, but shares certain morphological characters with A. lusca from the Galapagos Rift and A. muricola from the West Florida Escarpment, as well as with A. kexueae from the Manus Basin in the Southwest Pacific.