The Impact of Tracking Students in Mathematics on Middle School Student Achievement Outcomes

The purpose of this study was to explore whether and how tracking structures in mathematics courses at the middle school level relate to differences in achievement between white and black students. This study used propensity score matching to compare the achievement outcomes of students enrolled in advanced mathematics classes, with students of comparable ability and background enrolled in grade-level math classes. The study sample was comprised of 1,510 students. Results from the study show that enrollment in an advanced-math course was associated with statistically significant improvement in math achievement for average-ability students. In addition, study results show that increases in student achievement associated with average-ability black student enrollment in advanced-level math courses surpass the increases in math achievement outcomes associated with average-ability white student enrollment in advanced-level math courses. These findings have important equity implications because average-ability black students opt to enroll, or are disproportionately placed, in grade-level math as compared to average-ability white students. The findings suggest that increased enrollment of average-ability black and white students in advanced-level math would lead to a reduction in the racial math achievement gap and to improved math achievement outcomes for both black and white students

Text-mining of PubMed abstracts by natural language processing to create a public knowledge base on molecular mechanisms of bacterial enteropathogens

<p>Abstract</p> <p>Background</p> <p>The Enteropathogen Resource Integration Center (ERIC; <url>http://www.ericbrc.org</url>) has a goal of providing bioinformatics support for the scientific community researching enteropathogenic bacteria such as <it>Escherichia coli </it>and <it>Salmonella </it>spp. Rapid and accurate identification of experimental conclusions from the scientific literature is critical to support research in this field. Natural Language Processing (NLP), and in particular Information Extraction (IE) technology, can be a significant aid to this process.</p> <p>Description</p> <p>We have trained a powerful, state-of-the-art IE technology on a corpus of abstracts from the microbial literature in PubMed to automatically identify and categorize biologically relevant entities and predicative relations. These relations include: Genes/Gene Products and their Roles; Gene Mutations and the resulting Phenotypes; and Organisms and their associated Pathogenicity. Evaluations on blind datasets show an F-measure average of greater than 90% for entities (genes, operons, etc.) and over 70% for relations (gene/gene product to role, etc). This IE capability, combined with text indexing and relational database technologies, constitute the core of our recently deployed text mining application.</p> <p>Conclusion</p> <p>Our Text Mining application is available online on the ERIC website <url>http://www.ericbrc.org/portal/eric/articles</url>. The information retrieval interface displays a list of recently published enteropathogen literature abstracts, and also provides a search interface to execute custom queries by keyword, date range, etc. Upon selection, processed abstracts and the entities and relations extracted from them are retrieved from a relational database and marked up to highlight the entities and relations. The abstract also provides links from extracted genes and gene products to the ERIC Annotations database, thus providing access to comprehensive genomic annotations and adding value to both the text-mining and annotations systems.</p

The 3-Hydroxy-2-Butanone Pathway Is Required for Pectobacterium carotovorum Pathogenesis

Pectobacterium species are necrotrophic bacterial pathogens that cause soft rot diseases in potatoes and several other crops worldwide. Gene expression data identified Pectobacterium carotovorum subsp. carotovorum budB, which encodes the α-acetolactate synthase enzyme in the 2,3-butanediol pathway, as more highly expressed in potato tubers than potato stems. This pathway is of interest because volatiles produced by the 2,3-butanediol pathway have been shown to act as plant growth promoting molecules, insect attractants, and, in other bacterial species, affect virulence and fitness. Disruption of the 2,3-butanediol pathway reduced virulence of P. c. subsp. carotovorum WPP14 on potato tubers and impaired alkalinization of growth medium and potato tubers under anaerobic conditions. Alkalinization of the milieu via this pathway may aid in plant cell maceration since Pectobacterium pectate lyases are most active at alkaline pH

The FGGY carbohydrate kinase family : insights into the evolution of functional specificities

© The Author(s), 2011. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in PLoS Computational Biology 7 (2011): e1002318, doi:10.1371/journal.pcbi.1002318.Function diversification in large protein families is a major mechanism driving expansion of cellular networks, providing organisms with new metabolic capabilities and thus adding to their evolutionary success. However, our understanding of the evolutionary mechanisms of functional diversity in such families is very limited, which, among many other reasons, is due to the lack of functionally well-characterized sets of proteins. Here, using the FGGY carbohydrate kinase family as an example, we built a confidently annotated reference set (CARS) of proteins by propagating experimentally verified functional assignments to a limited number of homologous proteins that are supported by their genomic and functional contexts. Then, we analyzed, on both the phylogenetic and the molecular levels, the evolution of different functional specificities in this family. The results show that the different functions (substrate specificities) encoded by FGGY kinases have emerged only once in the evolutionary history following an apparently simple divergent evolutionary model. At the same time, on the molecular level, one isofunctional group (L-ribulokinase, AraB) evolved at least two independent solutions that employed distinct specificity-determining residues for the recognition of a same substrate (L-ribulose). Our analysis provides a detailed model of the evolution of the FGGY kinase family. It also shows that only combined molecular and phylogenetic approaches can help reconstruct a full picture of functional diversifications in such diverse families.This study was funded by NIH and DOE grants

Binary systems and their nuclear explosions

Peer ReviewedPreprin

The Impact of Tracking Students in Mathematics on Middle School Student Achievement Outcomes

The purpose of this study was to explore whether and how tracking structures in mathematics courses at the middle school level relate to differences in achievement between white and black students. This study used propensity score matching to compare the achievement outcomes of students enrolled in advanced mathematics classes, with students of comparable ability and background enrolled in grade-level math classes. The study sample was comprised of 1,510 students. Results from the study show that enrollment in an advanced-math course was associated with statistically significant improvement in math achievement for average-ability students. In addition, study results show that increases in student achievement associated with average-ability black student enrollment in advanced-level math courses surpass the increases in math achievement outcomes associated with average-ability white student enrollment in advanced-level math courses. These findings have important equity implications because average-ability black students opt to enroll, or are disproportionately placed, in grade-level math as compared to average-ability white students. The findings suggest that increased enrollment of average-ability black and white students in advanced-level math would lead to a reduction in the racial math achievement gap and to improved math achievement outcomes for both black and white students

The Impact of Tracking Students in Mathematics on Middle School Student Achievement Outcomes

The purpose of this study was to explore whether and how tracking structures in mathematics courses at the middle school level relate to differences in achievement between white and black students. This study used propensity score matching to compare the achievement outcomes of students enrolled in advanced mathematics classes, with students of comparable ability and background enrolled in grade-level math classes. The study sample was comprised of 1,510 students. Results from the study show that enrollment in an advanced-math course was associated with statistically significant improvement in math achievement for average-ability students. In addition, study results show that increases in student achievement associated with average-ability black student enrollment in advanced-level math courses surpass the increases in math achievement outcomes associated with average-ability white student enrollment in advanced-level math courses. These findings have important equity implications because average-ability black students opt to enroll, or are disproportionately placed, in grade-level math as compared to average-ability white students. The findings suggest that increased enrollment of average-ability black and white students in advanced-level math would lead to a reduction in the racial math achievement gap and to improved math achievement outcomes for both black and white students