Cux2-Positive Radial Glial Cells Generate Diverse Subtypes of Neocortical Projection Neurons and Macroglia

The mammalian neocortex is 6-layered structure that develops in an “inside-out” manner, with cells of the deep layers (Layers 5-6) born first. Cells of the superficial outer layers (Layers 2-4) are generated subsequently and must migrate past older born cells to their final laminar position. Pioneering transplant studies suggested a progressive lineage restriction model, which posits that early neural stem cells (or radial glial cells, RGCs) are multipotent and sequentially generate different types of cortical neurons based on birthdate. Recently published work from Franco et al. (2012) argues against this paradigm, and proposes the existence of a subclass of neural stem cells, fated from an early embryonic age to produce exclusively upper-layer neurons. They contend that at mouse embryonic day 10.5 (E10.5), when neocortical genesis is just beginning, an RGC subpopulation marked by expression of genetic transcription factor cut-like homeobox 2 (Cux2) is fated to produce exclusively upper layer (L2-4) cells. Cells not expressing Cux2 are fated to become deep layer (L5-6). We recently published work testing this model using Cre-mediated recombination. Our experiments demonstrated that both clonal and population levels of Cux2+ and Fezf2+ RGCs produce progeny that are multipotent and able to generate neurons, astrocytes, and oligodendrocytes. Here, we extend our lab’s previous work of the Cux2-positive and Fezf2-positive RGC lineages and find that E10.5 neocortical progenitors are able to generate diverse neuronal subtypes located throughout layers 2-6 as well as macroglia. Collectively, we find that Cux2-positive RGCs development does not differ from the progressive lineage restriction theory, and does not support the cell-intrinsic theory postulated by Franco et al. (2012)

Success Factors as Critical That Shape Agile Software Development Project Success

This study has implications for positive social change because organizations that understand the critical factors may be able to improve project management strategies and cost benefits leading to higher efficiency, profitability, and productivity thus benefiting management, employees, and customers. Information technology (IT) project success depends on having a project manager with effective decision-making, leadership, and project management skills. Project success also depends on completing the project in a given budget, time, and scope. However, there is a limited understanding of the lived experiences of agile managers and the following success factors: engineering, management, organization, and stakeholders. The purpose of this phenomenological study was to understand these lived experiences of 10 agile software development team project managers or leaders at global workplaces based in the United States. The research questions were focused on the effect of these success factors on agile software development project success. In accordance with nonrandom purposeful sampling strategies, a snowball technique was used to find more participants. An open-ended, e-mail questionnaire was created and sent to participants to collect data. The data were coded to discern themes or patterns. According to study results, agile software development team employs automate builds, continuous integration, and design patterns help reduce technical debt; good collaboration and communication skills are core to project success; product owner helps maximize business value delivered by team and priority and engage stakeholders; and sponsors help fund the project and other resources

Escargot

The nonlinear optical characteristics of semiconductors are studied near the two-photon biexciton resonance. Optical bistability is shown to happen below this resonance at very low light intensities