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Students enter college with widely varying levels of preparation. This is especially visible to faculty and administrators tasked with ensuring student success in core STEM courses and helping underrepresented students succeed. Flexible support strategies are needed. They must be timely and measurable so that limited funds can be optimally allocated. This paper reviews a program that addresses these concerns and is translatable to many higher education settings and disciplines. It is situated in a physics department at a large public research university in an urban city in the southern United States. A group of rotating faculty improved the success rate in an introductory physics course for non-physics majors. A diagnostic exam is used to assess students’ preparation in order to assign some to a peer-led supplementary recitation. An overview of program implementation and results is shared, along with strategies and suggested solutions to further address gaps in success rates in order to provide all students an equitable university experience and chance of success.

PurposeThis study examines the impact of participation in a STEM Enrichment Summer Bridge Program, funded by the NSF Houston-Louis Stokes Alliance for Minority Participation, on undergraduate student success outcomes, particularly for under-represented students.Design/methodology/approachThe study uses propensity score matching and logistic regression analysis to examine the effects of participation in the STEM enrichment program on graduation and retention in STEM after matching on baseline socio-demographic and pre-college characteristics.FindingsThe analysis found that program participation had a significant effect on increasing both the graduation rates and retention of under-represented minority students in STEM fields. In addition, results indicated that program participation had a particularly strong impact for Pell-eligible students in terms of course grades.Research limitations/implicationsData obtained for this study were limited to a single Hispanic-serving/Asian-serving institution, and therefore are not necessarily representative of the graduation and retention trends of the larger population of underrepresented minority (URM) students across the nation.Originality/valueThis study uniquely adds to the existing body of literature surrounding the retention of URM students in STEM fields by accounting for baseline variables, such as pre-college academic achievement and socio-demographic characteristics, that could lead to bias in estimating results. Specifically, this study addresses limitations of previous studies by comparing participants and non-participants of the STEM enrichment program who are matched on a selection of baseline characteristics.

The development of functionalized materials is needed to enable diverse applications. Protein-based materials are typically biocompatible and biodegradable and can exhibit a wide variety of useful mechanical properties. Most importantly, gene fusion enables facile incorporation of active proteins into the materials. However, many protocols rely on denaturing conditions to stimulate materials formation. These conditions would be expected to inactivate any appended functional proteins. This chapter describes methods to create protein fibers and films in a mild aqueous buffer near neutral pH. This facile, inexpensive single-pot approach to materials assembly does not require any special equipment. Also included in this chapter are methods to fuse fibers to form fiber bundles, and to use fibers for cell culture. Although these methods were developed to generate materials from the Drosophila Hox transcription factor Ultrabithorax, they may also work for other self-assembling proteins, many of which have sequence features in common with Ubx.

Sugars, such as sucrose and glucose, have been implicated in the regulation of diverse developmental events in plants and other organisms. We isolated an Arabidopsis (Arabidopsis thaliana) mutant, sugar-insensitive3 (sis3), that is resistant to the inhibitory effects of high concentrations of exogenous glucose and sucrose on early seedling development. In contrast to wild-type plants, sis3 mutants develop green, expanded cotyledons and true leaves when sown on medium containing high concentrations (e.g. 270 mm) of sucrose. Unlike some other sugar response mutants, sis3 exhibits wild-type responses to the inhibitory effects of abscisic acid and paclobutrazol, a gibberellic acid biosynthesis inhibitor, on seed germination. Map-based cloning revealed that SIS3 encodes a RING finger protein. Complementation of the sis3-2 mutant with a genomic SIS3 clone restored sugar sensitivity of sis3-2, confirming the identity of the SIS3 gene. Biochemical analyses demonstrated that SIS3 is functional in an in vitro ubiquitination assay and that the RING motif is sufficient for its activity. Our results indicate that SIS3 encodes a ubiquitin E3 ligase that is a positive regulator of sugar signaling during early seedling development.

A comprehensive gene collection for S. oneidensis was constructed using the lambda recombinase (Gateway) cloning system. A total of 3584 individual ORFs (85%) have been successfully cloned into the entry plasmids. To validate the use of the clone set, three sets of ORFs were examined within three different destination vectors constructed in this study. Success rates for heterologous protein expression of S. oneidensis His- or His/GST- tagged proteins in E. coli were approximately 70%. The ArcA and NarP transcription factor proteins were tested in an in vitro binding assay to demonstrate that functional proteins can be successfully produced using the clone set. Further functional validation of the clone set was obtained from phage display experiments in which a phage encoding thioredoxin was successfully isolated from a pool of 80 different clones after three rounds of biopanning using immobilized anti-thioredoxin antibody as a target. This clone set complements existing genomic (e.g., whole-genome microarray) and other proteomic tools (e.g., mass spectrometry-based proteomic analysis), and facilitates a wide variety of integrated studies, including protein expression, purification, and functional analyses of proteins both in vivo and in vitro.