1,212 research outputs found

    Decline in histone H5 phosphorylation during erythroid senescence in chick embryos

    Full text link
    Previous studies have implicated histone H5 dephosphorylation as a casual factor in genetic inactivation and chromatin condensation during erythroid senescence in adult chickens. We show that histone H5 phosphorylation declines in two stages as various cohorts of erythroid cells senesce in chick embryos. The first decline occurs between 5 and 6 days and coincides with the senescence of primitive erythrocytes. The second decline in H5 phosphorylation occurs between 17 and 19 days of chicken development, when the definitive erythrocytes undergo senescence and chromatin condensation. These results point to a role for histone dephosphorylation during the programed senescence of erythroid cells.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/29282/1/0000341.pd

    Can they row alone? practices that grow and support beginning principals

    Get PDF
    Beginning principals struggle with the complexity of the job, the limits of theirinstructional impact, the loneliness of leadership, and the existing culture’s resistance tochange. This is a problem in Henderson County Public Schools, in school systems acrossthe state of North Carolina, and nationwide. This problem negatively impacts beginningprincipals and their respective school communities because they struggle to navigateschool leadership transitions, to sustain district initiatives, and to experience consistentindividual growth. Students and parents have a right to expect competency from a schoolprincipal regardless of their lack of tenure, and districts must decide to be proactive inaccelerating the skills on new administrators. Effective mentoring programs can hastenthe competency of new school leaders.Given the absence of legislation, policy, and funding for beginning principal support inNorth Carolina, Henderson County Public Schools implemented a model designed togrow the leadership capacity of beginning principals in order that the impact of their service is maximized. The design of this purposeful intervention strategically matchesbeginning principals with mentors, while providing opportunities for professional growththrough self-assessment, reflection, and group learning.Using a Plan-Do-Study-Act (PDSA) cycle of improvement science, the scholarpractitionerscreated a scalable model for the mentoring of beginning principals.Experiencing the hire of six new principals in one school year, which markedapproximately 25% of the district’s school leadership, scholar-practitioners partneredwith the district to implement a structured support plan for these new administrators.Rather than leave their success to chance, Henderson County Public Schools recognizedand valued the importance of investing time and resources into leadership development.It is noteworthy that, following the period of initial research, the district has continuedwith and expanded the model of support. The results of this research inform not only thework of the partner school district, but also the practices of the current and futureleadership teams of North Carolina’s 115 systems, who guide over 2,400 principals asthey support more than 1.4 million students
    corecore