269 research outputs found

    Teachers as leaders in a knowledge society: encouraging signs of a new professionalism

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    [Abstract]: Challenges confronting schools worldwide are greater than ever,and, likewise, many teachers possess capabilities, talents, and formal credentials more sophisticated than ever. However, the responsibility and authority accorded to teachers have not grown significantly, nor has the image of teaching as a profession advanced significantly. The question becomes, what are the implications for the image and status of the teaching profession as the concept of knowledge society takes a firm hold in the industrialized world? This article addresses the philosophical underpinnings of teacher leadership manifested in case studies where schools sought to achieve the generation of new knowledge as part of a process of whole-school revitalization. Specifically, this article reports on Australian research that has illuminated the work of teacher leaders engaged in the IDEAS project, a joint school revitalization initiative of the University of Southern Queensland and the Queensland Department of Education and the Arts

    The Use of a Fractional Factorial Design to Determine the Factors That Impact 1,3-Propanediol Production from Glycerol by Halanaerobium Hydrogeniformans

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    In recent years, biodiesel, a substitute for fossil fuels, has led to the excessive production of crude glycerol. The resulting crude glycerol can possess a high concentration of salts and an alkaline pH. Moreover, current crude glycerol purification methods are expensive, rendering this former commodity a waste product. However, Halanaerobium hydrogeniformans, a haloalkaliphilic bacterium, possesses the metabolic capability to convert glycerol into 1,3-propanediol, a valuable commodity compound, without the need for salt dilution or adjusting pH when grown on this waste. Experiments were performed with different combinations of 24 medium components to determine their impact on the production of 1,3-propanediol by using a fractional factorial design. Tested medium components were selected based on data from the organism\u27s genome. Analysis of HPLC data revealed enhanced production of 1,3-propanediol with additional glycerol, pH, vitamin B12, ammonium ions, sodium sulfide, cysteine, iron, and cobalt. However, other selected components; nitrate ions, phosphate ions, sulfate ions, sodium:potassium ratio, chloride, calcium, magnesium, silicon, manganese, zinc, borate, nickel, molybdenum, tungstate, copper and aluminum, did not enhance 1,3-propanediol production. The use of a fractional factorial design enabled the quick and efficient assessment of the impact of 24 different medium components on 1,3-propanediol production from glycerol from a haloalkaliphilic bacterium

    Thermal Analysis of Adsorbed Poly(Methyl Methacrylate) on Silica

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    Modulated differential scanning calorimetry has been used to quantify the glass transitions of small, adsorbed amounts of poly (methyl methacrylate) (PMMA) on silica. While a relatively narrow, single glass transition was found for bulk PMMA, broader two-component transitions were found for the adsorbed polymer. a two-state model based on loosely bound polymer (glass transition similar to bulk) and more tightly bound polymer (glass transition centered around 156°C) was used to interpret the thermograms. on the basis of this model, the amount of tightly bound polymer was found to be approximately 1.3 mg/m 2, corresponding to a 1.1 nm thick layer. the change in heat capacity for the tightly bound polymer at the glass transition temperature was estimated to be about 16% of that of the bulk polymer. © 2006 American Chemical Society

    Conversion of Glycerol to 1,3-propanediol under Haloalkaline Conditions

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    A method of producing 1,3-propanediol. The method comprises fermenting a haloalkaliphilic species of Halanaerobium with a source of glycerol into 1,3-propanediol, at a pH of greater than about 10 and at a salt concentration of greater than about 5% w/v. Furthermore, with supplementation of vitamin B12, the yield of 1,3-propanediol to glycerol can be increased

    A Streamlined Strategy for Biohydrogen Production with Halanaerobium hydrogeniformans, an Alkaliphilic Bacterium

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    Biofuels are anticipated to enable a shift from fossil fuels for renewable transportation and manufacturing fuels, with biohydrogen considered attractive since it could offer the largest reduction of global carbon budgets. Currently, lignocellulosic biohydrogen production remains inefficient with pretreatments that are heavily fossil fuel-dependent. However, bacteria using alkali-treated biomass could streamline biofuel production while reducing costs and fossil fuel needs. An alkaliphilic bacterium, Halanaerobium hydrogeniformans, is described that is capable of biohydrogen production at levels rivaling neutrophilic strains, but at pH 11 and hypersaline conditions. H. hydrogeniformans ferments a variety of 5- and 6-carbon sugars derived from hemicellulose and cellulose including cellobiose, and forms the end products hydrogen, acetate, and formate. Further, it can also produce biohydrogen from switchgrass and straw pretreated at temperatures far lower than any previously reported and in solutions compatible with growth. Hence, this bacterium can potentially increase the efficiency and efficacy of biohydrogen production from renewable biomass resources
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