35 research outputs found
The Impact of Superintendent Turnover on Student Achievement in Rural Districts
The field has gained knowledge in the area of superintendent influence on student achievement; however, more research on superintendent turnover and its impact on organizational performance in a rural context is needed. Student achievement measures have become the primary indicator of school, principal, teacher, and student success (New York: Race to the Top State Scope of Work, 2011) and has become a measure of the superintendent’s performance. Using time series data analysis with twelve years of district data across the 21 schools studied, results indicated that superintendent turnover did impact student achievement. The motive of the superintendent, examined in this study through Carlson’s (1961) theory of internal versus external hire, suggested that superintendents hired from inside the district increased rural student achievement by 10.8 percent more than external hires. The means of the superintendent, examined in this study through Boyne and Dahya’s theory of Executive Succession, suggested that dependence of a school district on state aid served as a moderator. Student achievement in districts that are reliant on state aid as a revenue source were less impacted. The smaller the school, the less change in passing rates across succession events was observed
Estimating Trends of Common Raven Populations in North America, 1966–2018
Over the last half century, common raven (Corvus corax; raven) populations have increased in abundance across much of North America. Ravens are generalist predators known to depredate the eggs and young of several sensitive species. Quantifying raven population increases at multiple spatial scales across North America will help wildlife resource managers identify areas where population increases present the greatest risk to species conservation. We used a hierarchical Bayesian modeling approach to analyze trends of standardized raven counts from 1966 to 2018 using Breeding Bird Survey data within each Level I and II ecoregion of the United States and Canada. We also compared raven abundance within and outside the distributions of 9 sensitive or endangered species. Although we found substantial evidence that raven populations have increased across North America, populations varied in growth rates and relative abundances among regions. We found 73% of Level I (11/15) and II (25/34) ecoregions demonstrated positive annual population growth rates ranging from 0.2–9.4%. We found higher raven abundance inside versus outside the distributions of 7 of the 9 sensitive species included in our analysis. Gunnison sage-grouse (Centrocercus minimus) had the highest discrepancy, with 293% more ravens within compared to outside of their range, followed by greater sandhill crane (Antigone canadensis tabida; 280%), and greater sage-grouse (C. urophasianus; 204%). Only 2 species, least tern (Sternula antillarum) and piping plover (Charadrius melodus), indicated lower raven abundance within relative to outside their distributions. Our findings will help wildlife resource managers identify regional trends in abundance of ravens and anticipate which sensitive species are at greatest risk from elevated raven populations. Future research directed at identifying the underlying regional drivers of these trends could help elucidate the most appropriate and responsive management actions and, thereby, guide the development of raven population management plans to mitigate impacts to sensitive species
Establishment of an ES Cell-Derived Murine Megakaryocytic Cell Line, MKD1, with Features of Primary Megakaryocyte Progenitors
Because of the scarcity of megakaryocytes in hematopoietic tissues, studying megakaryopoiesis heavily relies on the availability of appropriate cellular models. Here, we report the establishment of a new mouse embryonic stem (ES) cell-derived megakaryocytic cell line, MKD1. The cells are factor-dependent, their cell surface immunophenotype and gene expression profile closely resemble that of primary megakaryocyte progenitors (MkPs) and they further differentiate along the megakaryocyte lineage upon valproic acid treatment. At a functional level, we show that ablation of SCL expression, a transcription factor critical for MkP maturation, leads to gene expression alterations similar to that observed in primary, Scl-excised MkPs. Moreover, the cell line is amenable to biochemical and transcriptional analyses, as we report for GpVI, a direct target of SCL. Thus, the MKD1 cell line offers a pertinent experimental model to study the cellular and molecular mechanisms underlying MkP biology and more broadly megakaryopoiesis
Abuse of developmentally disabled children: a preventative program
This project proposes a program designed to reduce the likelihood of abuse to children with developmental disabilities by teaching and training their parents. It begins with the evidence of abuse of children with developmental disabilities. The causes behind higher than average abuse rates are enumerated. The correlation between parental stress and abuse is covered. Violence prevention programs for schools, inmates and children are reviewed for viability. Components of these programs may be useful for a program focused on children with developmental disabilities. Violence prevention programs that serve children with developmental disabilities are reviewed. Possible solutions for reducing stress in general and in relation to raising a child with developmental disabilities are addressed