San Diego State University

About: San Diego State University is a education organization based out in San Diego, California, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 12418 authors who have published 27950 publications receiving 1192375 citations. The organization is also known as: SDSU & San Diego State College.

Specific language impairment and grammatical morphology: a discriminant function analysis.

Abstract: Discriminant function analysis was employed to determine if grammatical morpheme production could be used to classify preschool-age children with specific language impairment (SLI) and children with typically developing language skills. Three variables were included in the discriminant analysis: a finite verb morpheme composite, a noun morpheme composite, and mean length of utterance in morphemes. The children with SLI and age-matched controls were discriminated with high levels of accuracy, though the three variables did not yield identical classifications. Across two samples of typically developing children and children with SLI, the verb morpheme composite showed sensitivity exceeding 85% and specificity of 100%. In light of these results and growing evidence that problems with finite verb morphology continue into the school years in children with SLI, the verb morpheme composite was considered to hold promise as a clinical marker for SLI.

Changes in Soil Microbial Community Structure and Function in an Alpine Dry Meadow Following Spring Snow Melt

Abstract: Previous work in an alpine dry meadow in the Front Range of the Rocky Mountains has shown that microbial biomass is high during winter and declines rapidly as snow melts in the spring, and that this decline is associated with changes in temperature regime and substrate availability. In this study we tested the hypothesis that the summer and winter microbial communities differ in function and composition. Shifts in species composition between pre- and post-snowmelt communities were detected using reciprocal hybridization of community DNA; DNA extracted from soils sampled at different times was significantly less homologous relative to spatial replicates sampled at the same time. Fungal/bacterial ratios, as measured by direct microscopic counts and by substrate-induced respiration experiments with specific inhibitors, were higher in winter soils. Specific activity of cellulase (absolute cellulase activity per unit microbial biomass C) was higher in the winter soils than in summer soils, while specific amylase activity was not different between winter and summer. Based on most-probable number measurements, the use of the phenolic compound vanillic acid was highest in the winter, while the use of the amino acid glycine was lowest in the winter. Winter and summer soil respiration responded differently to temperature; at 0 degrees C, winter soils respired at a higher proportion of the 22 degrees C rate than did summer soils.

Assessment of sedentary behavior with the International Physical Activity Questionnaire.

Abstract: Purpose: This study explored definitions of sedentary behavior and examined the relationship between sitting time and physical inactivity using the sitting items from the International Physical Activity Questionnaire (IPAQ). Methods: Participants (N = 289, 44.6% male, mean age = 35.93) from 3 countries completed self-administered long- and short-IPAQ sitting items. Participants wore accelerometers; were classified as inactive (no leisure-time activity), insufficiently active, or meeting recommendations; and were classified into tertiles of sitting behavior. Results: Reliability of sitting time was acceptable for men and women. Correlations between total sitting and accelerometer counts/min <100 were significant for both long (r = .33) and short (r = .34) forms. There was no agreement between tertiles of sitting and the inactivity category (kappa = .02, P = .68). Conclusion: Sedentary behavior should be explicitly measured in population surveillance and research instead of being defined by lack of physical activity.

Professional Development Focused on Children's Algebraic Reasoning in Elementary School

Abstract: A yearlong experimental study showed positive effects of a professional development project that involved 19 urban elementary schools, 180 teachers, and 3735 students from one of the lowest performing school districts in California Algebraic reasoning as generalized arithmetic and the study of relations was used as the centerpiece for work with teachers in Grades 1?5 Participating teachers generated a wider variety of student strategies, including more strategies that reflected the use of relational thinking, than did nonparticipating teachers Students in participating classes showed significantly better understanding of the equal sign and used significantly more strategies reflecting relational thinking during interviews than did students in classes of nonparticipating teachers

Endoplasmic Reticulum Stress Gene Induction and Protection From Ischemia/Reperfusion Injury in the Hearts of Transgenic Mice With a Tamoxifen-Regulated Form of ATF6

Abstract: Ischemia/reperfusion (I/R) affects the integrity of the endoplasmic reticulum (ER), the site of synthesis and folding of numerous proteins. Therefore, I/R may activate the unfolded protein response (UPR), resulting in the induction of a collection of ER stress proteins, many of which are protective and function to resolve the ER stress. In this study, we showed that when mouse hearts were subjected to ex vivo I/R, the levels of 2 ER stress-inducible markers of the UPR, the ER-targeted cytoprotective chaperones glucose-regulated proteins 78 and 94 (GRP78 and GRP94), were increased, consistent with I/R-mediated UPR activation in the heart. The UPR-mediated activation of ATF6 (Activation of Transcription Factor 6) induces cytoprotective ER stress proteins, including GRP78 and GRP94. To examine whether ATF6 protects the myocardium from I/R injury in the heart, we generated transgenic (TG) mice featuring cardiac-restricted expression of a novel tamoxifen-activated form of ATF6, ATF6-MER. When NTG and ATF6-MER TG mice were treated with or without tamoxifen for 5 days, only the hearts from the tamoxifen-treated TG mice exhibited increased levels of many ER stress-inducible mRNAs and proteins; for example, GRP78 and GRP94 transcript levels were increased by 8- and 15-fold, respectively. The tamoxifen-treated TG mouse hearts also exhibited better functional recovery from ex vivo I/R, as well as significantly reduced necrosis and apoptosis. These results suggest that the UPR is activated in the heart during I/R and that, as a result, the ATF6 branch of the UPR may induce expression of proteins that can function to reduce I/R injury.