A case study of the perceptions of stakeholders regarding transformational leadership processes and structures implemented in a high poverty, high achieving school

Title from PDF of title page (University of Missouri--Columbia, viewed on October 31, 2012).The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file.Dissertation advisor: Dr. Barbara N. MartinIncludes bibliographical references.Vita.Ed. D. University of Missouri--Columbia 2012."July 2012"Boyd-Zaharias and Pate-Bain (2008) postulated that low achievement and high dropout rates among poor students continue to “plague” (p. 40) public schools in the United States; and elaborated further by stating, “our nation will profit by or pay for whatever they become” (p. 40). Chenoweth (2009a, 2009b) and Haycock (2001) shared that the country continues to move forward with reform efforts though the achievement gap between poor students and their non-poor peers does not tend to close, rather it widens. Therefore, the achievement gap between poor students and their peers, a problem of practice, is the focus of this narrative case study.Includes bibliographical reference

MOLLUSCICIDAL AND LARVICIDAL ACTIVITIES OF Atriplex inflata AERIAL PARTS AGAINST THE MOLLUSK Galba truncatula, INTERMEDIATE HOST OF Fasciola hepatica

Fasciolosis is a widespread parasitosis of farm live-stock in many developing countries. For this reason, it is necessary to search for new substances against parasitic diseases caused by flukes. Indeed, a wide variety of terrestrial plants have been subjected to chemical and pharmacological screening in order to discover their potential for human medicinal use. The molluscicidal and larvicidal activities of Atriplex inflata were tested on Galba truncatula and Fasciola hepatica larval stages infecting this snail in Tunisia. Phytochemical tests were conducted on extracts in order to establish a meaningful relationship with molluscicidal and larvicidal activities. The molluscicidal activity was evaluated by subjecting snails to sample aqueous solutions. Accordingly, hexane, ethyl acetate, methanol and methanol-water (8:2, v-v) were used as extraction solvents. As a result, hexane and ethyl acetate extracts showed potent activity, according to the World Health Organization, giving LC50 = 7.59 mg/L and 6.69 mg/L for hexane extracts of leaves and fruits, respectively. Ethyl acetate extracts gave LC50 = 5.90 mg/L and 7.32 mg/L for leaves and fruits, successively. Molluscicidal activities of powders were less potent on snails, but active according to the World Health Organization. Hexane and ethyl acetate extracts from leaves and fruits gave potent larvicidal activities with a delay rate exceeding 45.50% (45.50- 98.92%). Phytochemical tests showed that these activities may be attributed to the presence of triterpenoids and/or sterols

What leadership behaviors were demonstrated by the principal in a high poverty, high achieving elementary school?

Examined through the lens of leadership, were the behaviors of a principal as perceived by stakeholders. The following themes emerged: (1) Educating the Whole Child, with the subthemes: (a) providing basic needs; (b) academic interventions based on achievement data; (c) an emphasis on reading; (d) extended academic time; and (e) relationships; and (2) Synergy of Expectations, with the subthemes: (a) consistent student expectations; (b) increased staff accountability; and (c) community involvement. The researchers found that the principal by demonstrating behaviors as a change agent, a creator of vision, and a provider of necessary support and strategies, rather than adopting numerous programs, the school personnel were able to increase and sustain academic achievement of the students of poverty as well as their peers. Implications for principal practices, along with leadership preparatory programs are significant

Durability of Hardened Portland Cement Paste used for Oilwell Cementing

Durability of materials used for the completion of oilwell is of utmost importance for oil and gas industry. We carried out ageing tests on a hardened cement paste in two types of fluid by varying the experimental procedure. We show that the observed alterations are highly dependent on the way of conducting the tests. To correctly assess the long-term durability of cement-based materials, it is necessary to renew periodically the ageing fluid. By doing so, a severe impairment of the macroscopic properties of an hardened cement paste aged in a monthly-replaced brine can be observed

Cement-Polymer Composites for Oilwell Cementing

The selection of an optimal cementitious material is critical to maintain zonal isolation for the lifetime of oil & gas or gas storage wells not only for primary cementing but also after well abandonment. Polymer powder/cement composites present good mechanical and durability properties since polymer latex promotes improved adhesion and flexibility to the hardened cement paste. So, for well constructions in aggressive environment, polymer powder/cement composites would be good candidates. During the well construction, the cement slurry placement strongly depends on its rheological behaviour. In this paper, we studied rheological properties of polymer powder/cement composite suspensions: they present a transition from a gel to a liquid behaviour in oscillatory shear. The replacement of cement particles by polymer particles induces a decrease of the storage modulus in the gel state. The good quality of the polymer particle dispersion and their high affinity for cement particles were observed by Scanning Electron Microscopy (SEM). Solid state NMR (29Si and 27Al) and calorimetry allowed to highlight the influence of the polymer addition on both the hydration and hardening of the cement matrix. All these results helped us to understand the relations between the slurry composition, its rheological behaviour and the properties of the hardened materials which allowed us to design new cementing materials

Effect of annealing on the electrical properties of SrTiO3 thin films produced by ion beam sputtering

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Gene expression alterations in brains of mice infected with three strains of scrapie

<p>Abstract</p> <p>Background</p> <p>Transmissible spongiform encephalopathies (TSEs) or prion diseases are fatal neurodegenerative disorders which occur in humans and various animal species. Examples include Creutzfeldt-Jakob disease (CJD) in humans, bovine spongiform encephalopathy (BSE) in cattle, chronic wasting disease (CWD) in deer and elk, and scrapie in sheep, and experimental mice. To gain insights into TSE pathogenesis, we made and used cDNA microarrays to identify disease-associated alterations in gene expression. Brain gene expression in scrapie-infected mice was compared to mock-infected mice at pre-symptomatic and symptomatic time points. Three strains of mouse scrapie that show striking differences in neuropathology were studied: ME7, 22L, and Chandler/RML.</p> <p>Results</p> <p>In symptomatic mice, over 400 significant gene expression alterations were identified. In contrast, only 22 genes showed significant alteration in the pre-symptomatic animals. We also identified genes that showed significant differences in alterations in gene expression between strains. Genes identified in this study encode proteins that are involved in many cellular processes including protein folding, endosome/lysosome function, immunity, synapse function, metal ion binding, calcium regulation and cytoskeletal function.</p> <p>Conclusion</p> <p>These studies shed light on the complex molecular events that occur during prion disease, and identify genes whose further study may yield new insights into strain specific neuropathogenesis and ante-mortem tests for TSEs.</p