136 research outputs found

    Oracy matters:Introduction to the special issue on oracy

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    On-Farm Experimente - Leitfaden zur Planung und Durchführung

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    Durch den entwickelten Leitfaden wird gewährleistet, dass durch eine richtige Anlage/ Auswertung von Experimenten eine in den Betriebsablauf integrierte Weiterentwicklung von Anbauverfahren und –strategien erfolgen kann. So enthält der Leitfaden u.a. eine Anleitung zur Problemidentifikation und Formulierung relevanter Versuchsfragen, die unter den Bedingungen bzw. Einschränkungen von "On-Farm Experiments" realisiert werden können, eine Erläuterung der Grundprinzipien bei der Durchführung von Versuchen, eine Auswahl potenzieller Prüfmerkmale und -faktoren sowie Stufen der Prüffaktoren, Beispiele für Versuchsanlagen, Datenerhebung bzw. Auswertung/ Aussagefähigkeit und Dokumentation

    Improving the performance of alkali-activated slag mortar with electro/chemically treated carbon fiber textile

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    Alkali-activated slag is a widely used low-carbon binder. Incorporation of textile can mitigate the brittle weakness of alkali-activated composites. The bonding between fibers and matrix is critical for the performance of textile reinforced mortar. This paper is focused on the effect of different treatment methods on the bonding properties of carbon fiber in alkali-activated slag. The interfacial shear strength of fiber bundles in matrix was determined by the pull-out test. The flexural strength of the reinforced mortar was evaluated by a repeated bending. A scanning electron microscopy test was performed to characterize the interfacial properties of the fiber bundles. The results show that the interfacial shear strength of carbon fibers in matrix is improved by the electroplating with calcium silica slurry (CSS), impregnation in different solutions, and plasma treatments. An electroplating in CSS has the best improvement in the bonding strength with an increase by 620%. The CSS treatment increases the maximum flexural strength of CFT reinforced mortar with 22.5% and 30% at 7 and 28 d respectively, and it significantly inhibits the crack growth under the cyclic loading. This effect becomes more significant after a longer curing age. The electroplating treatment eliminates the cracks in the interface of fiber yarns. Slag reacts with the plated portlandite to strengthen the bonding between mortar and fiber bundles, so it has a better inhibiting effect on the crack growth after a longer curing

    Grain legume yields are as stable as other spring crops in long-term experiments across northern Europe

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    Grain legumes produce high-quality protein for food and feed, and potentially contribute to sustainable cropping systems, but they are grown on only 1.5% of European arable land. Low temporal yield stability is one of the reasons held responsible for the low proportion of grain legumes, without sufficient quantitative evidence. The objective of this study was to compare the yield stability of grain legumes with other crop species in a northern European context and accounting for the effects of scale in the analysis and the data. To avoid aggregation biases in the yield data, we used data from long-term field experiments. The experiments included grain legumes (lupin, field pea, and faba bean), other broad-leaved crops, spring, and winter cereals. Experiments were conducted in the UK, Sweden, and Germany. To compare yield stability between grain legumes and other crops, we used a scale-adjusted yield stability indicator that accounts for the yield differences between crops following Taylor's Power Law. Here, we show that temporal yield instability of grain legumes (30%) was higher than that of autumn-sown cereals (19%), but lower than that of other spring-sown broad-leaved crops (35%), and only slightly greater than spring-sown cereals (27%). With the scale-adjusted yield stability indicator, we estimated 21% higher yield stability for grain legumes compared to a standard stability measure. These novel findings demonstrate that grain legume yields are as reliable as those of other spring-sown crops in major production systems of northern Europe, which could influence the current negative perception on grain legume cultivation. Initiatives are still needed to improve the crops agronomy to provide higher and more stable yields in future.Peer reviewe

    Re-designing organic grain legume cropping systems using systems agronomy

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    Crop production in Europe is intensive, highly specialized and responsible for some negative environmental impacts, raising questions about the sustainability of agricultural systems. The (re)integration of grain legumes into European agricultural systems could contribute to the transition to more sustainable food production. While the general benefits from legume cultivation are widely known, there is little evidence on how to re-design specific cropping systems with legumes to make this option more attractive to farmers. The objectives of this study were to describe the constraints and opportunities of grain legume production perceived by farmers, explain the agronomic impacts of current grain legume cropping, explore technical options to improve grain legume agronomy, and to re-design current grain legume cropping systems in a participatory process with farmers. A co-design approach was implemented with farmers, advisors and scientists on 25 farms in northern Germany, that were part of two large demonstration networks of about 170 farms supporting grain legumes across Germany. We used the DEED research cycle (Describe, Explain, Explore and Design) as a conceptual framework combining on-farm research, crop rotation modelling, and on-station experiments. From it, we identified nine agronomic practices that either were novel or confirmed known strategies under new conditions, to re-design grain legume cropping systems at the field and farm level. The practices included (i) inter-row hoeing, (ii) direct seeding into a cover-crop, (iii) species-specific inoculation, (iv) cover crops to reduce leaching, (v) reduced tillage, (vi) soybean for increased gross margins, (vii) cultivars for food and feed use, (viii) flexible irrigation, (ix) grain legumes with cover crop to enhance subsequent crop yields. We also demonstrate how to complement knowledge of farmers' perceptions (Describe step) and formal knowledge from classical on-station experiments and modelling (Explain step) with on-farm research including the local views of farmers (Explore step) to identify tailored options for specific farm contexts rather than prescriptive solutions (Design step) to intensify legume production. This approach therefore contrasts with traditional methods that are often solely participatory and qualitative or model/experimental-based and quantitative. Hence, our results provide new insights in how to re-design cropping systems using a combination of participatory and quantitative approaches. While participatory approaches are common in developing countries, this study shows their potential in an industrialized context with large-scale farmers in Europe. These novel findings can be used as a starting point for further adaptations of cropping systems and contribute to making grain legume production economically and environmentally more sustainable.Peer reviewe

    A cropping system assessment framework-Evaluating effects of introducing legumes into crop rotations

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    Methods are needed for the design and evaluation of cropping systems, in order to test the effects of introducing or reintroducing crops into rotations. The interaction of legumes with other crops (rotational effects) requires an assessment at the cropping system scale. The objective of this work is to introduce a cropping system framework to assess the impacts of changes in cropping systems in a participatory approach with experts, i.e., the integration of legumes into crop rotations and to demonstrate its application in two case studies. The framework consists of a rule-based rotation generator and a set of algorithms to calculate impact indicators. It follows a three-step approach: (i) generate rotations, (ii) evaluate crop production activities using environmental, economic and phytosanitary indicators, and (iii) design cropping systems and assess their impacts. Experienced agronomists and environmental scientists were involved at several stages of the framework development and testing in order to ensure the practicability of designed cropping systems. The framework was tested in Vastra Gotaland (Sweden) and Brandenburg (Germany) by comparing cropping systems with and without legumes. In both case studies, cropping systems with legumes reduced nitrous oxide emissions with comparable or slightly lower nitrate-N leaching, and had positive phytosanitary effects. In arable systems with grain legumes, gross margins were lower than in cropping systems without legumes despite taking pre-crop effects into account. Forage cropping systems with legumes had higher or equivalent gross margins and at the same time higher environmental benefits than cropping systems without legumes. The framework supports agronomists to design sustainable legume-supported cropping systems and to assess their impacts. (C) 2015 The Authors. Published by Elsevier B.V.Peer reviewe

    Sending Granny to Chiang Mai: debating global outsourcing of care for the elderly

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    This article ties in with existing discussions on global care chains, family separation and the devaluation of social-reproductive work. We explore the new trend of outsourcing care for the elderly to countries with lower wages. We base our analysis on the debate in the German press and supplement it with insights from ethnographic field observations in two care homes in Thailand. We identify a discourse of abandonment, which shows how outsourcing the care of the elderly unsettles the privilege of sedentarism that is often taken for granted in the Global North. Furthermore, the newspaper articles tend to villainize people who seek care for their loved ones abroad. We argue that both discourses foster a neoliberal rationale of individualized responsibility and obfuscate the deep systemic roots of the care crisis in the Global North. However, by extending the discussion on outsourcing care for the elderly beyond the dominant media discourses, we envisage a rich potential for provoking political debate on the revaluation of care

    Grain legume production and use in European agricultural systems

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    ISBN(print) 978-0-12-812419-2; Editor DL SparksThere is a great demand for high-protein materials for livestock feed in Europe and European agriculture has a deficit of about 70% high-protein materials of which 87% is met by imported soybean and soy meal. This reflects the fact that grain legumes are currently under represented in European agriculture and produced on only 1.5% of the arable land in Europe compared with 14.5%on aworldwide basis. Several grain legumes have the potential to replace at least some of the soya currently used in the diets of monogastric animals, ruminants, and fish. There are also opportunities for greater use of legumes in new foods. Here we review the contribution of ecosystem services by grain legumes in European agriculture startingwith provisioningservices in termsof food and feed and moving on to the contribution theymake to both regulating and supporting serviceswhich are in part due to the diversity which these crops bring to cropping systems. We explore the need to understand grain legume production on the time scale of a rotation rather than a cropping season in order to value and manage the agronomic challenges of weed, pests, and diseases alongside themaintenance or improvement of soil structure, soil organic matter, and nutrient cycling. A review of policy interventions to support grain legumes reveals that until very recently these have failed to make a difference in Europe. We contrast the European picture with the interventions that have allowed the development of grain legume production in both Canada and Australia. Whether farmers choose to grow more legumes will depend on market opportunities, the development of supply chains, and policy support aswell as technicalimprovementsof grainlegumeproductionsuchas breeding of new varieties and management development to improve yield stability. However, to really increase the production of grain legumes in Europe, the issues are far more wide reaching than agronomy or subsidy and require a fundamental rethinking of value chains to move grain legumes from being niche products to mainstream commodities.Peer reviewe

    A framework for developing an evidence-based, comprehensive tobacco control program

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    BACKGROUND: Tobacco control is an area where the translation of evidence into policy would seem to be straightforward, given the wealth of epidemiological, behavioural and other types of research available. Yet, even here challenges exist. These include information overload, concealment of key (industry-funded) evidence, contextualization, assessment of population impact, and the changing nature of the threat. METHODS: In the context of Israel's health targeting initiative, Healthy Israel 2020, we describe the steps taken to develop a comprehensive tobacco control strategy. We elaborate on the following: a) scientific issues influencing the choice of tobacco control strategies; b) organization of existing evidence of effectiveness of interventions into a manageable form, and c) consideration of relevant philosophical and political issues. We propose a framework for developing a plan and illustrate this process with a case study in Israel. RESULTS: Broad consensus exists regarding the effectiveness of most interventions, but current recommendations differ in the emphasis they place on different strategies. Scientific challenges include integration of complex and sometimes conflicting information from authoritative sources, and lack of estimates of population impact of interventions. Philosophical and political challenges include the use of evidence-based versus innovative policymaking, the importance of individual versus governmental responsibility, and whether and how interventions should be prioritized.The proposed framework includes: 1) compilation of a list of potential interventions 2) modification of that list based on local needs and political constraints; 3) streamlining the list by categorizing interventions into broad groupings of related interventions; together these groupings form the basis of a comprehensive plan; and 4) refinement of the plan by comparing it to existing comprehensive plans. CONCLUSIONS: Development of a comprehensive tobacco control plan is a complex endeavour, involving crucial decisions regarding intervention components. "Off the shelf" plans, which need to be adapted to local settings, are available from a variety of sources, and a multitude of individual recommendations are available. The proposed framework for adapting existing approaches to the local social and political climate may assist others planning for smoke-free societies. Additionally, this experience has implications for development of evidence-based health plans addressing other risk factors
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