1,919 research outputs found

    Questions of quality in repositories of open educational resources: a literature review

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    Open educational resources (OER) are teaching and learning materials which are freely available and openly licensed. Repositories of OER (ROER) are platforms that host and facilitate access to these resources. ROER should not just be designed to store this content – in keeping with the aims of the OER movement, they should support educators in embracing open educational practices (OEP) such as searching for and retrieving content that they will reuse, adapt or modify as needed, without economic barriers or copyright restrictions. This paper reviews key literature on OER and ROER, in order to understand the roles ROER are said or supposed to fulfil in relation to furthering the aims of the OER movement. Four themes which should shape repository design are identified, and the following 10 quality indicators (QI) for ROER effectiveness are discussed: featured resources; user evaluation tools; peer review; authorship of the resources; keywords of the resources; use of standardised metadata; multilingualism of the repositories; inclusion of social media tools; specification of the creative commons license; availability of the source code or original files. These QI form the basis of a method for the evaluation of ROER initiatives which, in concert with considerations of achievability and long-term sustainability, should assist in enhancement and development. Keywords: open educational resources; open access; open educational practice; repositories; quality assuranc

    There\u27ll Come A Day Of Reckoning

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    https://digitalcommons.library.umaine.edu/mmb-me/1270/thumbnail.jp

    Carbon and Hydrogen Contents of Short-Rotation Biomass of Five Hardwood Species

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    Carbon, hydrogen, and ash contents were determined on three-year-old, short-rotation trees of autumn olive, black alder, black locust, eastern cottonwood, and sycamore. These plantations were established on marginal agricultural land that was not suitable for food production in Midwestern United States. Test results indicated that elemental analysis varied among species, planting site, and spacing. Black locust had the highest hydrogen content, black alder had the highest carbon content, and eastern cottonwood possessed the greatest ash content. The hydrogen content was higher at bottomland than upland, while the carbon content and ash content were both higher on upland as opposed to bottomland sites. The hydrogen content was higher at narrow spacing, while carbon content was higher at wide spacing. Conversely, hydrogen was not significantly affected by the stem portion, while both carbon and ash contents of the wood, bark, and branches mixture portion were higher than those of the wood portion

    Cyclic catalytic upgrading of chemical species using metal oxide materials

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    Processes are disclosure which comprise alternately contacting an oxygen-carrying catalyst with a reducing substance, or a lower partial pressure of an oxidizing gas, and then with the oxidizing gas or a higher partial pressure of the oxidizing gas, whereby the catalyst is alternately reduced and then regenerated to an oxygenated state. In certain embodiments, the oxygen-carrying catalyst comprises at least one metal oxide-containing material containing a composition having one of the following formulas: (a) Ce.sub.xB.sub.yB'.sub.zB''O.sub..delta., wherein B=Ba, Sr, Ca, or Zr; B'=Mn, Co, or Fe; B''=Cu; 0.01<x<0.99; 0<y<0.6; 0<z<0.5; and 1<.delta.<2.2; (b) Sr.sub.vLa.sub.wB.sub.xB'.sub.yB''.sub.zO.sub..delta., wherein B=Co or Fe; B'=Al or Ga; B''=Cu; 0.01<v<1.4; 0.1<w<1.6; 0.1<x<1.9; 0.1<y<0.9; 0<z<2.2; and 3<.delta.<5.5)

    Systematic Approach to Identifying Deeply Buried Archeological Deposits

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    This project is designed to assist cultural resource specialists involved in Nebraska Department of Transportation (NDOT) and the Federal Highway Administration (FHWA) project planning and development. The goal was to develop Geographic Information System (GIS) data layers that spatially delineate different landform-sediment assemblages (LSAs) and depict the associated geologic potential for buried cultural deposits in select watersheds in Nebraska. The Nebraska Buried Sites GIS resource will allow planners and cultural resource specialists to determine whether future project areas are likely to be free of deeply buried sites or whether subsurface exploration is necessary

    Cyclic Catalytic Upgrading of Chemical Species Using Metal Oxide Materials

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    Processes are disclosure which comprise alternately contacting an oxygen-carrying catalyst with a reducing substance, or a lower partial pressure of an oxidizing gas, and then with the oxidizing gas or a higher partial pressure of the oxidizing gas, whereby the catalyst is alternately reduced and then regenerated to an oxygenated state. In certain embodiments, the oxygen-carrying catalyst comprises at least one metal oxide-containing material containing a composition having the following formulas: (a) Ce(sub x)B(sub y)B'(sub z)B''O(sub gamma; wherein B=Ba, Sr, Ca, or Zr; B'=Mn, Co, and/or Fe; B''=Cu; 0.01<x<0.99; 0<y<0.6; 0<z<0.5; (b) Ce(sub 1-x-y) Ni(sub x) B(sub y) O(sub 2-*), wherein B=Zr, Ba, Ca, La, or K; 0.02<x<0.1; 0<y<0.1; and 0.02<*<0.15; and 1<delta<2.2 and (c) coal ash either as a catalyst material itself or as a support for said unary or binary metal oxides

    Rural Communities in Transition and Sustainable Regional Development

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    Mining and farming have been important industries to the Australian economy since colonial times but the industries have generally operated in separate regions with limited overlaps. Over the last decade mining activity has surpassed agriculture in both return on investment and contribution to gross domestic product (GDP) and farming has continued to lose its share of economic contribution. To date, most mining activity has been in remote and regional areas of Australia where the deposits are richest, but sophisticated extractive processes and high returns are now making deposits viable which hither to have been considered marginal, many of which are in communities where farming has been the main industry. This paper will consider case study sites where mining is increasingly encroaching on what has been traditionally productive farming land. For some communities, mining is welcomed as an important off-farm income, for others, mining is viewed as an environmental and social threat to the agricultural industry. The stresses and strains as well as the opportunities presented by transitional rural economies will be considered

    Effects of Forage Type, Storage Method, and Moisture Level in Crop Residues Mixed with Modified Distillers Grains

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    Two growing experiments compared effects of feeding a diet consisting of cornstalks or wheat straw and modified distillers grains when ensiled or mixed fresh daily. Wheat-straw based diets also were compared at different moisture levels (50% and 70%) when ensiled and mixed daily. In Experiment 1, steers fed ensiled diets had greater DMI compared to diets mixed daily. Moisture level and crop residue type had no effect on steer performance. In Experiment 2, steers were offered the supplements and a hay mix to determine palatability and forage replacement. Moisture level had no effect, cornstalks were consumed better than wheat straw, and steers fed freshly mixed diets gained more and were more efficient than those fed ensiled mixes

    Association of Inactive Myostatin in Piedmontese-Influenced Steers and Heifers on Performance and Carcass Traits at Different Endpoints

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    Performance and carcass traits were evaluated using Piedmontese-influenced calf-fed steers and yearling heifers genotyped for zero, one, or two copies (homozygous active, heterozygous, or homozygous inactive, respectively) of the inactive myostatin allele. Steers and heifers had similar responses across genotypes in performance and carcass traits evaluated at different endpoints. Inactive myostatin decreased DMI, final BW (live), and ADG (live). Increased dressing percentage resulted in increased carcass-adjusted ADG and improved feed conversion for cattle with inactive myostatin. Cattle with inactive myostatin are leaner with larger LM area when finished to equal carcass weight

    The role of cytokinins in clubroot disease

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    Clubroot (Plasmodiophora brassicae) is a pathogen of Brassicaceae that causes significant reductions in yield as a consequence of gall formation in the root and hypocotyl of infected plants. The pathogen hijacks host vascular cambium development, and cytokinins are implicated in this process. This paper uses transcriptomics and metabolomics to investigate changes in cytokinin metabolism during gall formation of clubroot-infected Arabidopsis thaliana. RNASeq analysis of infected tissue showed that host cytokinin metabolism was strongly down-regulated both at the onset and late stages of gall formation. Expression of host genes associated with cytokinin biosynthesis, signalling, degradation and conjugation was strongly repressed. Analysis of cytokinin precursors, active components and conjugates by microanalytical techniques was consistent with these transcriptional responses. Two isopentenyltransferase genes associated with cytokinin biosynthesis are present in the P. brassicae genome and are expressed throughout gall formation. The impact of pathogen-derived cytokinins on the total cytokinin content of infected tissue and host gene expression was minimal in wild type plants. However, infection of ipt1;3;5;7 mutants that are severely restricted in their ability to synthesise active cytokinins led to an increase in expression of host cytokinin-responsive genes. We interpret these results as indicating that P. brassicae can synthesise small amounts of cytokinin, but this has little impact on the host plant as the ipt1;3;5;7 phenotype is not rescued. Intriguingly, plasmodial development was slowed and spore viability reduced in these mutants indicating a potential role for cytokinins in plasmodial development
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