Insights Into the Mineralogy and Surface Chemistry of Extracellular Biogenic S0 Globules Produced by Chlorobaculum tepidum

Elemental sulfur (S0) is produced and degraded by phylogenetically diverse groups of microorganisms. For Chlorobaculum tepidum, an anoxygenic phototroph, sulfide is oxidized to produce extracellular S0 globules, which can be further oxidized to sulfate. While some sulfur-oxidizing bacteria (e.g., Allochromatium vinosum) are also capable of growth on commercial S0 as an electron donor, C. tepidum is not. Even colloidal sulfur sols, which appear indistinguishable from biogenic globules, do not support the growth of C. tepidum. Here, we investigate the properties that make biogenic S0 globules distinct from abiotic forms of S0. We found that S0 globules produced by C. tepidum and abiotic S0 sols are quite similar in terms of mineralogy and material properties, but the two are distinguished primarily by the properties of their surfaces. C. tepidum’s globules are enveloped by a layer of organics (protein and polysaccharides), which results in a surface that is fundamentally different from that of abiotic S0 sols. The organic coating on the globules appears to slow the aging and crystallization of amorphous sulfur, perhaps providing an extended window of time for microbes in the environment to access the more labile forms of sulfur as needed. Overall, our results suggest that the surface of biogenic S0 globules may be key to cell–sulfur interactions and the reactivity of biogenic S0 in the environment

A survey of practices for the use of electronic health records to support research recruitment

Electronic health records (EHRs) provide great promise for identifying cohorts and enhancing research recruitment. Such approaches are sorely needed, but there are few descriptions in the literature of prevailing practices to guide their use. A multidisciplinary workgroup was formed to examine current practices in the use of EHRs in recruitment and to propose future directions. The group surveyed consortium members regarding current practices. Over 98% of the Clinical and Translational Science Award Consortium responded to the survey. Brokered and self-service data warehouse access are in early or full operation at 94% and 92% of institutions, respectively, whereas, EHR alerts to providers and to research teams are at 45% and 48%, respectively, and use of patient portals for research is at 20%. However, these percentages increase significantly to 88% and above if planning and exploratory work were considered cumulatively. For most approaches, implementation reflected perceived demand. Regulatory and workflow processes were similarly varied, and many respondents described substantive restrictions arising from logistical constraints and limitations on collaboration and data sharing. Survey results reflect wide variation in implementation and approach, and point to strong need for comparative research and development of best practices to protect patients and facilitate interinstitutional collaboration and multisite research

Field courses narrow demographic achievement gaps in ecology and evolutionary biology.

Disparities remain in the representation of marginalized students in STEM. Classroom-based experiential learning opportunities can increase student confidence and academic success; however, the effectiveness of extending learning to outdoor settings is unknown. Our objectives were to examine (a) demographic gaps in ecology and evolutionary biology (EEB) major completion, college graduation, and GPAs for students who did and did not enroll in field courses, (b) whether under-represented demographic groups were less likely to enroll in field courses, and (c) whether under-represented demographic groups were more likely to feel increased competency in science-related tasks (hereafter, self-efficacy) after participating in field courses. We compared the relationships among academic success measures and demographic data (race/ethnicity, socioeconomic status, first-generation, and gender) for UC Santa Cruz undergraduate students admitted between 2008 and 2019 who participated in field courses (N = 941 students) and who did not (N = 28,215 students). Additionally, we administered longitudinal surveys to evaluate self-efficacy gains during field-based versus classroom-based courses (N = 570 students). We found no differences in the proportion of students matriculating at the university as undecided, proposed EEB, or proposed other majors across demographic groups. However, five years later, under-represented students were significantly less likely to graduate with EEB degrees, indicating retention rather than recruitment drives disparities in representation. This retention gap is partly due to a lower rate of college completion and partly through attrition to other majors. Although under-represented students were less likely to enroll in field courses, field courses were associated with higher self-efficacy gains, higher college graduation rates, higher EEB major retention, and higher GPAs at graduation. All demographic groups experienced significant increases in self-efficacy during field-based but not lecture-based courses. Together, our findings suggest that increasing the number of field courses and actively facilitating access to students from under-represented groups can be a powerful tool for increasing STEM diversity