129 research outputs found

    Evaluation of the Effect of Agricultural Management on Energy Yield and Greenhouse Gas Emission Reduction of Bioenergy Production Chains

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    The role of energy crops in reducing fossil energy use and greenhouse gas emission is much debated. To improve decision making on the use of crops for producing bioenergy, a tool (Energy Crop Simulation Model or E-CROP) has been developed to calculate 1) sustainable crop dry matter yield levels as function of agricultural inputs, and 2) gross and net energy yield and greenhouse gas emission reduction, covering the entire bioenergy production chain from sowing to distribution of bioenergy. E-CROP can be applied to a wide range of crops, soils, climatic conditions, management choices, and conversion technologies. This paper describes E-CROP and focuses on its application on four arable crops, as cultivated on two contrasting sites in the Netherlands (potato and sugar beet for bioethanol, winter oilseed rape for biodiesel and silage maize for bioelectricity) and on the effect of crop management (viz. irrigation and nitrogen fertilisation). In all situations, gross energy output exceeded total energy input. Calculated for an average situation, net energy yield ranged from 45 to 140 GJ·ha-1. Lowering irrigation and/or fertilisation input levels generally resulted in a reduction of net energy yields. The net reduction of greenhouse gas emissions in the average situation ranged from 0.60 to 6.5 t CO2-eq·ha-1. In general, N2O emission from nitrogen fertiliser caused large variations in the net reduction of greenhouse gas emission, which even became negative in some situations. Lowering nitrogen fertilisation to levels that are suboptimal for net energy yields enhanced the net reduction in greenhouse gas emission, implicating that both goals cannot be optimised simultaneously. Agricultural knowledge is important for optimising the outputs of bioenergy production chains

    Van HELP naar Waterpas?

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    De HELP-tabel wordt al gedurende vele decennia gebruikt voor het berekenen van nat- en droogteschade in de landbouw. Daarbij wordt al jarenlang gepraat over een aanpassing, verbetering, verdieping of vervanging ervan. Nu biedt het Waterpas-model de mogelijkheid om nat- en droogteschade op heldere en goed onderbouwde wijze te berekenen voor zowel de gewasopbrengst als de gevolgen voor de bedrijfseconomie (zoals dat ook getoetst is in het veenweidegebied, voor de polders Zegveld en Oud-Kamerik). De voorspelling van toekomstige gevolgen van veranderend waterbeheer, mestbeleid, klimaatverandering en de effecten op waterkwaliteit kunnen ook met een toekomstige versie van Waterpas worden bereken

    Zoeken naar een indicator voor mobiel N in de bodem

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    De nitraatconcentraties in het grondwater zijn op veel plaatsen in Nederland te hoog. Verandering in bemestingsbeleid zullen naar verwachting effect hebben op nitraatuitspoeling naar grondwater en oppervlaktewater. Monitoren van nitraatconcentraties in het grondwater is echter zeer arbeidsintensief. Daarom is gezocht naar een bodemparameter, die reageert op veranderingen in bemesting en daarom als indicator voor verandering in nitraatuitspoeling kan dienen. Bodemmonsters zijn genomen in langjarige bemestingsproeven en diverse bodemparameters zijn gemeten en vergeleken. Geen van de parameters gaf een duidelijke reactie op bemesting. De nitraatconcentratie in het grondwater reageerde wel. Dit lijkt de beste indicator voor uitspoeling te zijn

    Are You Being Rhetorical? A Description of Rhetorical Move Annotation Tools and Open Corpus of Sample Machine-Annotated Rhetorical Moves

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    Writing analytics has emerged as a sub-field of learning analytics, with applications including the provision of formative feedback to students in developing their writing capacities. Rhetorical markers in writing have become a key feature in this feedback, with a number of tools being developed across research and teaching contexts. However, there is no shared corpus of texts annotated by these tools, nor is it clear how the tool annotations compare. Thus, resources are scarce for comparing tools for both tool development and pedagogic purposes. In this paper, we conduct such a comparison and introduce a sample corpus of texts representative of the particular genres, a subset of which has been annotated using three rhetorical analysis tools (one of which has two versions). This paper aims to provide both a description of the tools and a shared dataset in order to support extensions of existing analyses and tool design in support of writing skill development. We intend the description of these tools, which share a focus on rhetorical structures, alongside the corpus, to be a preliminary step to enable further research, with regard to both tool development and tool interaction</jats:p

    Pathogenic Variants in the Myosin Chaperone UNC-45B Cause Progressive Myopathy with Eccentric Cores

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    The myosin-directed chaperone UNC-45B is essential for sarcomeric organization and muscle function from Caenorhabditis elegans to humans. The pathological impact of UNC-45B in muscle disease remained elusive. We report ten individuals with bi-allelic variants in UNC45B who exhibit childhood-onset progressive muscle weakness. We identified a common UNC45B variant that acts as a complex hypomorph splice variant. Purified UNC-45B mutants showed changes in folding and solubility. In situ localization studies further demonstrated reduced expression of mutant UNC-45B in muscle combined with abnormal localization away from the A-band towards the Z-disk of the sarcomere. The physiological relevance of these observations was investigated in C. elegans by transgenic expression of conserved UNC-45 missense variants, which showed impaired myosin binding for one and defective muscle function for three. Together, our results demonstrate that UNC-45B impairment manifests as a chaperonopathy with progressive muscle pathology, which discovers the previously unknown conserved role of UNC-45B in myofibrillar organization

    Conferred resistance to Botrytis cinerea in Lilium by overexpression of the RCH10 chitinase gene

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    The production of ornamentals is an important global industry, with Lilium being one of the six major bulb crops in the world. The international trade in ornamentals is in the order of £60-75 billion and is expected to increase worldwide by 2-4 % per annum. The continued success of the floriculture industry depends on the introduction of new species/cultivars with major alterations in key agronomic characteristics, such as resistance to pathogens. Fungal diseases are the cause of reduced yields and marketable quality of cultivated plants, including ornamental species. The fungal pathogen Botrytis causes extreme economic losses to a wide range of crop species, including ornamentals such as Lilium. Agrobacterium-mediated transformation was used to develop Lilium oriental cv. ‘Star Gazer’ plants that ectopically overexpress the Rice Chitinase 10 gene (RCH10), under control of the CaMV35S promoter. Levels of conferred resistance linked to chitinase expression were evaluated by infection with Botrytis cinerea; sporulation was reduced in an in vitro assay and the relative expression of the RCH10 gene was determined by quantitative Reverse-Transcriptase PCR. The extent of resistance to Botrytis, compared to that of the wild type plants, showed a direct correlation with the level of chitinase gene expression. Transgenic plants grown to flowering showed no detrimental phenotypic effects associated with transgene expression. This is the first report of Lilium plants with resistance to Botrytis cinerea generated by a transgenic approach
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