508 research outputs found

    Student voices in academic writing: PsychLiverpool a community for meaning making

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    The practice and expectations of academic communication are changing and blogging provides a socially liberating mechanism through which to support the development of student writing and literacy. The study reported here examines the impact of an academic–student partnership in supporting the development of student discourse. Anonymous feedback gathered from both the contributors and readers of the student blog, PsychLiverpool, was analysed using automated text analysis. The analysis identified that high levels of positive emotion were associated with PsychLiverpool. Students valued its capacity to trigger thinking and insight, and the social and networking relationships the blog offered. PsychLiverpool empowered students to expand their learning networks outside their classroom and to peer-network by connecting them with like-minded students and academics. By providing students with safe opportunities to develop their skills and networks, it fulfilled their needs for affiliation and achievement, power, and reward. The particular advantage of PsychLiverpool was that in operating outside traditional university processes of assessment and feedback, students were more motivated to write about and engage with academic language on their own terms

    Efecto de la compactación de suelos sobre el rendimiento del maíz en tres localidades de Costa Rica

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    Diagnosticar las condiciones intermedias de compactación en el suelo es importante para evitar condiciones extremas, las cuales a menudo son visibles en el campo. Esto se puede lograr con curvas de rendimiento de cultivos, en respuesta a grados diferentes de compactación, medidos con parámetros cuantitativos. Se seleccionaron parcelas de terreno de 20x80 m en Guachipelín, el Rodeo y Puriscal en Costa Rica, con un paisaje adecuado para estudiar el efecto de la erosión sobre la producción de maíz, en diferentes zonas de las parcelas, con niveles iniciales de fertilización diferentes. Las zonas contaron con una caracterización de propiedades físicas de los suelos utilizables para medir su compactación. Las regresiones del modelo Royleigh para el rendimiento de maíz vs. RP (resistencia a la penetración), DA (densidad aparente) y HV- 1,5MPa (humedad volumétrica a una succión de 1,5 MPa); y las funciones logarítmicas y cuadráticas para CH (conductividad hidráulica), han identificado valores intermedios con funciones diagnósticas potenciales para lugares individuales y sistemas compuestos de compactación. Las parcelas de referencia (rendimiento cero) junto con los datos experimentales contribuyeron con regresiones interpoladas confiables (r2 > 0,9 para 100% de fertilización). Los r2 para 100% de fertilización fueron mayores que aquellos sin fertilización porque la fertilización reducía el componente de variabilidad debido a la fertilidad. El uso del RR (rendimiento relativo) permitió unir datos de lugares diferentes y las regresiones compuestas resultantes facilitaron la comparación de los lugares. La relación entre los rendimientos con 100% de fertilización de Guachipelín: Rodeo: Puriscal fue 1:0,52:0,47, y se explica mediante la interacción entre el RP, el HV-1,5MPa, el DA, y el CH que dio 1:0,49:0,42, con 4 parámetros; y entre el RP, HV-1,5MPa y CH que dio 1:0,61:0,46, logrado con 3 parámetros

    Efecto de la compactación de suelos sobre el rendimiento del maíz en tres localidades de Costa Rica

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    Diagnosticar las condiciones intermedias de compactación en el suelo es importante para evitar condiciones extremas, las cuales a menudo son visibles en el campo. Esto se puede lograr con curvas de rendimiento de cultivos, en respuesta a grados diferentes de compactación, medidos con parámetros cuantitativos. Se seleccionaron parcelas de terreno de 20x80 m en Guachipelín, el Rodeo y Puriscal en Costa Rica, con un paisaje adecuado para estudiar el efecto de la erosión sobre la producción de maíz, en diferentes zonas de las parcelas, con niveles iniciales de fertilización diferentes. Las zonas contaron con una caracterización de propiedades físicas de los suelos utilizables para medir su compactación. Las regresiones del modelo Royleigh para el rendimiento de maíz vs. RP (resistencia a la penetración), DA (densidad aparente) y HV- 1,5MPa (humedad volumétrica a una succión de 1,5 MPa); y las funciones logarítmicas y cuadráticas para CH (conductividad hidráulica), han identificado valores intermedios con funciones diagnósticas potenciales para lugares individuales y sistemas compuestos de compactación. Las parcelas de referencia (rendimiento cero) junto con los datos experimentales contribuyeron con regresiones interpoladas confiables (r2 > 0,9 para 100% de fertilización). Los r2 para 100% de fertilización fueron mayores que aquellos sin fertilización porque la fertilización reducía el componente de variabilidad debido a la fertilidad. El uso del RR (rendimiento relativo) permitió unir datos de lugares diferentes y las regresiones compuestas resultantes facilitaron la comparación de los lugares. La relación entre los rendimientos con 100% de fertilización de Guachipelín: Rodeo: Puriscal fue 1:0,52:0,47, y se explica mediante la interacción entre el RP, el HV-1,5MPa, el DA, y el CH que dio 1:0,49:0,42, con 4 parámetros; y entre el RP, HV-1,5MPa y CH que dio 1:0,61:0,46, logrado con 3 parámetros

    Grassland soil tillage by three implements in an Ultisol and its physical and hydropedological implications

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    Mediante un estudio en el campo, se determinó el efecto de la labranza mecanizada con 3 implementos sobre la compactación, las variables físicas e hidropedológicas de un Ultisol dedicado a la ganadería, ubicado en San Mateo, Alajuela. Se seleccionó un lote de aproximadamente 10 000 m2, se dividió en 16 parcelas iguales (650 m2 cada una), y se aleatorizó la mecanización con 3 diferentes implementos correspondientes a los tratamientos, a partir de una parcela y un diseño experimental irrestricto al azar. Como tratamientos se estableció un área sin labranza (T), y labranza mediante un palín mecánico (PM), un arado de cincel (AC) o un subsolador (S). Cuarenta días después de la aplicación de los tratamientos se determinó la resistencia a la penetración cada 5 cm hasta los 50 cm de profundidad, y la humedad gravimétrica, densidad aparente y de partículas, infiltración y conductividad hidráulica fueron evaluadas, todas ellas en los primeros 10 cm de profundidad. Se encontró un descenso en la compactación del suelo, expresada como resistencia a la penetración, para los tratamientos de mecanización, y reportó el tratamiento palín mecánico (PM) con los valores más bajos. Este mismo tratamiento incrementó la infiltración acumulada (38,70±3,60 mm a los 150 min) de manera significativa, al comparar con la obtenida en el tratamiento testigo (0,09±0,02 mm a los 150 min). No se encontró diferencias significativas entre los tratamientos de mecanización para densidad aparente, porosidad y espacio aéreo, pero sí con respecto al tratamiento T. El tratamiento subsolador (S) propició los valores más elevados de conductividad hidráulica, sin diferencias estadísticas del resto de tratamientos (p>0,05).A field study was conducted to test the effects of soil tillage with 3 different implements on compaction, physical and hydropedological properties of an Ultisol under cattle production, located in San Mateo, Alajuela. An area of approximately 10 000 m2 was selected and divided into 16 plots (650 m2 each) and was tilled with 3 different implements corresponding to the treatments, following an unrestricted random experimental design, with a plot as experimental unit. Soil without tillage (T), tillage by spader plow (PM), tillage by chisel plow (C) or tillage by subsoiler (S) were established as treatments. Forty days after tillage treatments, soil penetration resistance every 5 cm up to 50 cm deep was assessed, and gravimetric moisture content, bulk and particle density, water infiltration and hydraulic conductivity, all of them up to the first 10 cm deep, all of them were measured. Soil compaction, expressed as soil penetration resistance, was reduced by tillage treatments; the lowest values for soil compaction were found in the spader plow treatment (PM). This same treatment enhanced cumulated infiltration (38.70±3.60 mm at 150 min) significantly, comparing with those obtained in T treatment (0.09±0.02 mm at 150 min). No significant differences were found among tillage treatments for bulk density, total porosity and airspace, but comparing with control treatment (T) they were found. Subsoiler treatment (S) favored the highest values for hydraulic conductivity, but no significant differences with the other treatments were found (p>0.05).UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Centro de Investigaciones Agronómicas (CIA

    Blueberry Research Progress Reports

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    The 1989 edition of the Blueberry Research Progress Reports was prepared for the Maine Wild Blueberry Commission and the University of Maine Wild Blueberry Advisory Committee by researchers with the Maine Agricultural Experiment Station and Maine Cooperative Extension Service at the University of Maine, Orono. Projects in this report include: 1. Control of Secondary Blueberry Pests 2. Monitory Methods, Economic Injury Levels, and Action Thresholds of Secondary Blueberry Pests 3. Control of Blueberry Maggot 4. Phosphorus Dose/Response Curve 5. Nitrogen-Phosphorus Study 6. Multiple Cropping of Wild Stands 7. Changes in Sugars and Organic Acids of Blueberries During Development 8. Investigation of Preprocess Changes That Could Lead to the Development of a Simple and Inexpensive Method to Measure Preprocess Berry Spoilage 9. Development of Simple and Less Expensive Methods to Analyze Pesticides Used on Maine and Canadian Blueberries 10. Evaluation and Modification of Commercial Wipers 11. Effect of Rate and Formulation of Hexazinone on Bunchberry 12. Bracken Fern Control Alternatives 13. Evaluation of Hexazinone with Spot Treatments of Glyphosate Sethoxydim or Fluazifop-P for Bunchgrass Control 14. Directed Sprays of Glyphosate for Bunchberry Control 15. Evaluation of Norflurazon with or without Hexazinone for Bunchgrass Control 16. Selective Wiper and Mechanical Control of Dogbane 17. Evaluation of Sulfonyl Urea Herbicides for Bunchberry Control 18. Seedling Pruning Study 19. Evaluation of Sethoxydim in Lowbush Blueberry Fields 20. Blueberry Extension Program 21. Pollination of the Low-bush Blueberry by Native Bees 22. Postharvest Fungi of Lowbush Blueberries 23. Effects of Pruning Methods on Mummy Berry Incidenc

    Blueberry Progress Reports

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    The 1982 edition of the Blueberry Progress Reports was prepared for the Maine Blueberry Commission and the University of Maine Blueberry Advisory Committee by researchers with the Maine Life Sciences and Agriculture Experiment Station and Maine Cooperative Extension Service at the University of Maine, Orono. Projects in this report include: 1. Introduction 2. Blueberry IPM Program 3. Guthion Drift Study 4. Control, Biology, and Ecology of Insects 5. Blueberry Diseases: Incidence and Control 6. Physiology and Culture of the Lowbush Blueberry 7. Weed Control in Lowbush Blueberries 8. Pruning Blueberrie

    Genome Sequence of Cronobacter sakazakii BAA-894 and Comparative Genomic Hybridization Analysis with Other Cronobacter Species

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    The genus Cronobacter (formerly called Enterobacter sakazakii) is composed of five species; C. sakazakii, C. malonaticus, C. turicensis, C. muytjensii, and C. dublinensis. The genus includes opportunistic human pathogens, and the first three species have been associated with neonatal infections. The most severe diseases are caused in neonates and include fatal necrotizing enterocolitis and meningitis. The genetic basis of the diversity within the genus is unknown, and few virulence traits have been identified.We report here the first sequence of a member of this genus, C. sakazakii strain BAA-894. The genome of Cronobacter sakazakii strain BAA-894 comprises a 4.4 Mb chromosome (57% GC content) and two plasmids; 31 kb (51% GC) and 131 kb (56% GC). The genome was used to construct a 387,000 probe oligonucleotide tiling DNA microarray covering the whole genome. Comparative genomic hybridization (CGH) was undertaken on five other C. sakazakii strains, and representatives of the four other Cronobacter species. Among 4,382 annotated genes inspected in this study, about 55% of genes were common to all C. sakazakii strains and 43% were common to all Cronobacter strains, with 10-17% absence of genes.CGH highlighted 15 clusters of genes in C. sakazakii BAA-894 that were divergent or absent in more than half of the tested strains; six of these are of probable prophage origin. Putative virulence factors were identified in these prophage and in other variable regions. A number of genes unique to Cronobacter species associated with neonatal infections (C. sakazakii, C. malonaticus and C. turicensis) were identified. These included a copper and silver resistance system known to be linked to invasion of the blood-brain barrier by neonatal meningitic strains of Escherichia coli. In addition, genes encoding for multidrug efflux pumps and adhesins were identified that were unique to C. sakazakii strains from outbreaks in neonatal intensive care units

    IL-4 Amplifies the Pro-Inflammatory Effect of Adenosine in Human Mast Cells by Changing Expression Levels of Adenosine Receptors

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    Adenosine inhalation produces immediate bronchoconstriction in asthmatics but not in normal subjects. The bronchospastic effect of adenosine is largely mediated through adenosine-induced mast cell activation, the mechanism of which is poorly understood due to limitations in culturing human primary mast cells. Here, we show that human umbilical cord blood -derived mast cells incubated with the Th2 cytokine IL-4 develop increased sensitivity to adenosine. Potentiation of anti-IgE- induced and calcium ionophore/PMA-induced degranulation was augmented in mast cells cultured with IL-4, and this effect was reduced or abolished by pre-treatment with A2BsiRNA and selective A2B receptor antagonists, respectively. IL-4 incubation resulted in the increased expression of A2B and reduced expression of A2A adenosine receptors on human mast cells. These results suggest that Th2 cytokines in the asthmatic lung may alter adenosine receptor expression on airway mast cells to promote increased responsiveness to adenosine

    1993 Progress Reports

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    The 1993 Progress Reports which contain Blueberry Tax Supported Weed Management and Pruning Project Reports, and CSRS Supported Weed Management and Pruning Project Reports, pertain to and report on research conducted in 1992. They were prepared for the Maine Wild Blueberry Commission and the University of Maine Wild Blueberry Advisory Committee by researchers at the University of Maine, Orono. Projects in this report include: Progress Reports 1. Effects of Irrigation on Low bush Blueberry Yield and Quality 2. Economics of Investing in Irrigation for Lowbush Blueberries 3. Diammonium Phosphate Study 4. Phosphorus Dose/Response Curve 5. Winter Injury Protection by Potassium 6. Multiple Cropping of Wild Stands 7. Effect of Boron on Lowbush Blueberry Fruit Set and Yield 8.Determination of Pesticide Residue Levels in Freshly Harvested and Processed Lowbush Blueberries 9. Effects of Calcium Salts and Citric Acids on the Quality of Canned Lowbush Blueberries- missing 10. Investigation of PreProcess Changes- missing 11. The Effect of Fertilization and Irrigation on Blueberry Fruit Control - missing 12. Pollination Ecology of Lowbush Blueberry in Maine 13. Control of Secondary Blueberry Pests 14. Control of Blueberry Maggot 15. Biology and Action Thresholds of Secondary Blueberry Pests 16. Cold-Hardiness of Native Lowbush Blueberries 17. Design, Fabrication, and Testing of an Experimental Sterilizer for Blueberry Fields 18. Canned Product Quality - Heat Resistant Molds 19. Sanitation for Disease Control Blueberry Tax Supported Weed Management and Pruning Project Reports 20. Evaluation of Postemergence Applications of Tribenuron Methyl for Bunchberry Control 21. Comparison of Poast and Select for Suppression of Bunchgrass 22. Effect of Time of Fall Pruning on Growth and Productivity of Blueberries. and Evaluation of Infrared Burner to Prune Blueberries 23. Evaluation of Velpar impregnated DAP for weed control 24. Thresholds of Dogbane and Bracken Fern for Mechanical and Chemical Control in Lowbush Blueberry Fields 25. Effect of Time and Rate of Application of Clopyralid for Control of Vetch in Lowbush Blueberries 26. Hexazinone Ground Water Survey 27. Composting Blueberry Processing Waste 28. Hexazinone Movement in a Blueberry Soil in Maine CSRS Supported Weed Management and Pruning Project Reports 29. Evaluation of the Suitability of Remote Sensing to Evaluate Plant Cover in Lowbush Blueberry Fields 30. Obstruction Removal in Lowbush Blueberry Fields 31. Evaluation of Pressurized Rope Wick Wick Master Wiper for Treating Weeds Growing Above Lowbush Blueberries 32. Evaluation of Infrared Burner for Weed Control 33. Blueberry Extension Education Program Base Miscellaneous 34. Comparison of N, NP, and NPK Fertilizers to Correct Nitrogen and Phosphorus Deficienc

    Maine Blueberry Advisory Committee Research Report

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    The 1990 edition of the Maine Blueberry Advisory Committee Research Reports was prepared for the Maine Wild Blueberry Commission and the University of Maine Wild Blueberry Advisory Committee by researchers with the Maine Agricultural Experiment Station and Maine Cooperative Extension Service at the University of Maine, Orono. Projects in this report include: 1. Biology and action thresholds of secondary blueberry pests 2. Control of blueberry maggot 3. Control of secondary blueberry pests 4. Application of steam as a method of controlling secondary pest insects on lowbush blueberry: a feasibility study 5. Pollination of the lowbush blueberry by native bees 6. Nitrogen-phosphorus study 7. Potassium study 8. Multiple cropping of wild stands 9. Phosphorus dose/response curve 10. Improvement in the color and texture of the canned blueberry 11. The effect of fertilization and irrigation on blueberry fruit quality 12. Investigation of preprocess changes (chemical, microbiological, and/or physical) that could lead to the development of a simple and inexpensive method to measure preprocess berry spoilage 13. The effect of postharvest handling on the dietary fiber and ellagic acid content of lowbush blueberries 14. Determination of pesticide residue levels in freshly harvested and processed lowbush blueberries 15. Evaluation of Defoliating Diseases 16. Vacuum Sanitation for Disease Control 17. Evaluation and modification of commercial herbicide applications 18. Evaluation of the suitability of remote sensing to evaluate plant cover in lowbush blueberry fields 19. Evaluation of Sethoxydin (POAST) in lowbush blueberry fields 20. Seedling pruning study 21. Evaluation of norflurazon (SOLICAM) with or without hexazinone (VELPAR) for bunchberry control 22. Selective wiper and mechanical control of dogbane and bracken fern 23. Evaluation of norflurazon (SOLICAM) in fall vs spring for oatgrass control 24. Evaluation of sulfonyl urea herbicides for bunchberry control 25. Evaluation of postemergence applications of DPX-L5300 for bunchberry control 26. Effect of time of application and formulation of hexazinone (VELPAR) on blueberry and bunchberry 27. Investigations of lowbush blueberry fruit-bud cold hardiness 28. The economics of investing in irrigation for lowbush blueberries 29. Effects of irrigation on lowbush blueberry yield and quality 30. Groundwater and surface water development for blueberry irrigation 31. Design, fabrication and testing of an experimental sterilizer for blueberry field
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