Analysis of Postdoctoral Training Outcomes That Broaden Participation in Science Careers.

Postdoctoral training is an optimal time to expand research skills, develop independence, and shape career trajectories, making this training period important to study in the context of career development. Seeding Postdoctoral Innovators in Research and Education (SPIRE) is a training program that balances research, teaching, and professional development. This study examines the factors that promote the transition of postdocs into academic careers and increase diversity in science, technology, engineering, and mathematics. Data indicate that SPIRE scholars (n = 77) transition into faculty positions at three times the national average with a greater proportion of underrepresented racial minorities (URMs) and females represented among SPIRE scholars. Logistic regression models indicate that significant predictors are the intended career track at the start of the postdoctoral training and the number of publications. Factors necessary for successful transition are teaching experience as independent instructors, professional development opportunities, and the experience of balancing teaching with research. Scholars' continued commitment to increasing diversity in their faculty roles was demonstrated by their attainment of tenure-track positions at minority-serving institutions, continued mentorship of URMs, and engagement with diversity initiatives. These results suggest that a postdoctoral program structured to include research, teaching, and diversity inclusion facilitates attainment of desired academic positions with sustained impacts on broadening participation.

The development and implementation of an instrument to assess students' data analysis skills in molecular biology.

Developing visual literacy skills is an important component of scientific literacy in undergraduate science education. Comprehension, analysis, and interpretation are parts of visual literacy that describe related data analysis skills important for learning in the biological sciences. The Molecular Biology Data Analysis Test (MBDAT) was developed to measure students' data analysis skills connected with scientific reasoning when analyzing and interpreting scientific data generated from experimental research. The skills analyzed included basic skills, such as identification of patterns and trends in data and connecting a method that generated the data, and advanced skills, such as distinguishing positive and negative controls, synthesizing conclusions, determining if data supports a hypothesis, and predicting alternative or next-step experiments. Construct and content validity were established and calculated statistical parameters demonstrate that the MBDAT is valid and reliable for measuring students' data analysis skills in molecular and cell biology contexts. The instrument also measures students' perceived confidence in their data interpretation abilities. As scientific research continues to evolve in complexity, interpretation of scientific information in visual formats will continue to be an important component of scientific literacy. Thus science education will need to support and assess students' development of these skills as part of students' scientific training.

A case-based approach increases student learning outcomes and comprehension of cellular respiration concepts.

This study investigated student learning outcomes using a case-based approach focused on cellular respiration. Students who used the case study, relative to students who did not use the case study, exhibited a significantly greater learning gain, and demonstrated use of higher-order thinking skills. Preliminary data indicate that after engaging with the case study, students were more likely to answer a question addressing misconceptions about cellular respiration correctly when compared with students who did not use the case study. More rigorous testing is needed to fully elucidate whether case-based learning can effectively clarify student misconceptions related to biological processes.

Correlation between env V1/V2 region diversification and neutralizing antibodies during primary infection by simian immunodeficiency virus sm in rhesus macaques.

Evolution of the domain encoding the V1/V2 variable region of the simian immunodeficiency virus sm (SIVsm) envelope (env) gene was analyzed in relation to route of virus challenge, virus load, and neutralizing antibody (NAb) titers during primary infection of rhesus macaques with the pathogenic SIVsmE660 isolate. In this model system animals are initially infected with multiple viruses as evidenced by the presence of multiple V1/V2 genotypic variants that could be resolved by using a heteroduplex tracking assay (HTA). Overlapping subsets of the multiple variants were established in each animal. There was no selection for the establishment of specific variants in comparing intravenous- and intrarectal-challenged macaques at week 2 postinfection, suggesting that no genotypic selection occurred at the mucosal surface. There was an initial period of significant stability of the V1/V2 variants. Macaques challenged intravenously displayed subsequent V1/V2 diversification significantly earlier than macaques challenged intrarectally and well past the initial resolution of viremia. The time when SIVsmE660-specific NAbs reached a threshold titer of 100 was significantly correlated with the timing of V1/V2 diversification, even though antibodies to the Env protein could be detected much earlier. The time when NAbs reached a titer of 400 was significantly correlated with virus load late in infection. These results show that the route of infection affects the timing of V1/V2 diversification and that this diversification is correlated with the maturation of a specific NAb response. However, prior immunization capable of priming an anamnestic Env antibody response did not accelerate V1/V2 diversification. This result suggests that diversification of the SIV env V1/V2 region is the result of a type-specific antibody response.

Matrix-fibrinogen enhances wound closure by increasing both cell proliferation and migration.

Fibrinogen (FBG) assembles into matrix fibrils of fibroblasts, lung and mammary epithelial cells, but not endothelial cells. Furthermore, cryptic beta15-21 residues are exposed in FBG fibrils with no evidence of thrombin or plasmin proteolysis. Herein, the effects of FBG on migration and proliferation of wounded dermal fibroblasts were investigated. FBG preassembled into matrix prior to scrape-wounding induced 3H-thymidine incorporation 8-fold and shortened the time to wound closure 1.6-fold +/- 0.1-fold. FBG added immediately after wounding did not enhance either response. Fibroblast growth factor-2/platelet-derived growth factor (FGF-2/PDGF) stimulated cell proliferation 2.2-fold for FGF-2 and 3.2-fold for PDGF and wound closure 1.5-fold +/- 0.1-fold in the absence of matrix-FBG. Surprisingly, exogenous growth factors had negligible effect on wound closure and cell proliferation already enhanced by matrix-FBG. Matrix-FBG-enhanced wound closure required active assembly of an FBG-fibronectin matrix, engagement of alphavbeta3, and FBG Aalpha-RGDS572-575 integrin recognition sites; Aalpha-RGDF95-98 sites were not sufficient for matrix-FBG assembly, enhanced wound closure, or cell proliferation. Although Bbeta1-42 was not necessary for matrix assembly, it was required for matrix-FBG-enhanced cell migration. These data indicate that FBG serves as an important matrix constituent in the absence of fibrin formation to enhance wound repair and implicate Bbeta1-42 as a physiologic inducer of signal transduction to promote an intermediate state of cell adhesion and a migratory cell phenotype.