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Different developmental mathematics programs are offered at various institutions across the United States. Many vary from state to state, and even college to college within states. One of the designs that has emerged as a frontrunner is the co-requisite model. This pilot study builds on previous success of the model by exploring the effect of pass rates when the placement range for co-requisite courses is expanded. The goal is for the pilot results to help indicate whether or not more students should place directly into the co-requisite model, bypassing the prerequisite stand alone. Results are promising, and continue to show success for this model.

Infantile (fetal and neonatal) megakaryocytes (Mks) have a distinct phenotype consisting of hyperproliferation, limited morphogenesis, and low platelet production capacity. These properties contribute to clinical problems that include thrombocytopenia in neonates, delayed platelet engraftment in recipients of cord blood stem cell transplants, and inefficient ex vivo platelet production from pluripotent stem cell-derived Mks. The infantile phenotype results from deficiency of the actin-regulated coactivator, MKL1, which programs cytoskeletal changes driving morphogenesis. As a strategy to complement this molecular defect, we screened pathways with the potential to affect MKL1 function and found that DYRK1A inhibition dramatically enhanced Mk morphogenesis in vitro and in vivo. Dyrk1 inhibitors rescued enlargement, polyploidization, and thrombopoiesis in human neonatal Mks. Mks derived from induced pluripotent stem cells responded in a similar manner. Progenitors undergoing Dyrk1 inhibition demonstrated filamentous actin assembly, MKL1 nuclear translocation, and modulation of MKL1 target genes. Loss-of-function studies confirmed MKL1 involvement in this morphogenetic pathway. Expression of Ablim2, a stabilizer of filamentous actin, increased with Dyrk1 inhibition, and Ablim2 knockdown abrogated the actin, MKL1, and morphogenetic responses to Dyrk1 inhibition. These results delineate a pharmacologically tractable morphogenetic pathway whose manipulation may alleviate clinical problems associated with the limited thrombopoietic capacity of infantile Mks., Introduction Human megakaryocytes (Mks) undergo dramatic changes during ontogenic progression from fetal through adult stages. These changes include diminishing proliferation and a concomitant increase in adult-type morphogenesis (1-3). Adult-type morphogenesis [...]

Microbial-driven N turnover is important in regulating N fertilizer use efficiency through the secretion of metabolites like glycolipids. Currently, our understanding of the potential of glycolipids to partially reduce N fertilizer use and the effects of glycolipids on crop yield and N use efficiency is still limited. Here, a three-year in situ field experiment was conducted with seven treatments: no fertilization (CK); chemical N, phosphorus and potassium (NPK); NPK plus glycolipids (N+PKT); and PK plus glycolipids with 10% (0.9 N+PKT), 20% (0.8 N+PKT), 30% (0.7 N+PKT), and 100% (PKT) N reduction. Compared with NPK, glycolipids with 0–20% N reduction did not significantly reduce maize yields, and also increased N uptake by 6.26–11.07%, but no significant changes in grain or straw N uptake. The N resorption efficiency under 0.9 N+PKT was significantly greater than that under NPK, while the apparent utilization rates of N fertilizer and partial factor productivity of N under 0.9 N+PKT were significantly greater than those under NPK. Although 0.9 N+PKT led to additional labor and input costs, compared with NPK, it had a greater net economic benefit. Our study demonstrates the potential for using glycolipids in agroecosystem management and provides theoretical support for optimizing fertilization strategies. [ABSTRACT FROM AUTHOR]

Aims: N2O emitted by agricultural ecosystems has a great impact on global warming and climate change. The use of controlled-release fertilizers (CRF) can decrease greenhouse gas emissions. However, the general patterns and variability of nitrogen functional genes in response to CRF associated with N2O emission have not been synthesized under climate change. Methods: We investigated the effects of CRF, elevated CO2 concentration (EC), elevated temperature (ET), and their combination on N2O emission, enzyme activities and gene abundances. Results: We found that the cumulative N2O emissions was in the range of 0.39–1.65 kg·ha−1 in the wheat-growing season, accounting for 0.54%–2.29% of the total nitrogen input. N2O emissions were considerably positively correlated with ammonia-oxidizing bacteria (AOB) at elongation stage. CRF inputs significantly decreased N2O emissions by 29 − 66% compared with urea due to decreased AOB abundance and inhibited nitrite reductase activities at elongation stage. EC significantly decreased N2O emissions by 30 − 50% likely resulting from the inhibition in nitrifying and denitrifying community compared with ambient CO2 concentration. ET significantly increased N2O emissions by increasing N mineralization in wheat soil under CRF due to higher NH4+-N and NO3−-N concentration in wheat soil at elongation stage. In addition, ECET had antagonistic effect on N2O emissions. CRF had no significant effect on wheat yield under climate change scenarios. Conclusions: CRF decreased the cumulative N2O emissions under climate change scenarios. This is critical for understanding the responses of N2O emissions from wheat soil under CRF to future CO2 enrichment and warming for the establishment of mitigation and adaptation policies. [ABSTRACT FROM AUTHOR]