228 research outputs found

    An On-Farm experimental philosophy for farmer-centric digital innovation

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    In this paper, we review learnings gained from early On-Farm Experiments (OFE) conducted in the broad acre Australian grain industry from the 1990s to the present day. Although the initiative was originally centered around the possibilities of new data and analytics in precision agriculture, we discovered that OFEs could represent a platform for engaging farmers around digital technologies and innovation. Insight from interacting closely with farmers and advisors leads us to argue for a change in the ways we approach OFE research. Acknowledging that conditions have changed and drawing from business and social sciences, we suggest that OFE approaches today should develop aspects related to skill development, value generation and value sharing, the social dimension of change, and a renewed focus on farmer-centric research to better bridge industry requirements and scientist inputs

    Megahertz serial crystallography

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    The new European X-ray Free-Electron Laser is the first X-ray free-electron laser capable of delivering X-ray pulses with a megahertz inter-pulse spacing, more than four orders of magnitude higher than previously possible. However, to date, it has been unclear whether it would indeed be possible to measure high-quality diffraction data at megahertz pulse repetition rates. Here, we show that high-quality structures can indeed be obtained using currently available operating conditions at the European XFEL. We present two complete data sets, one from the well-known model system lysozyme and the other from a so far unknown complex of a β-lactamase from K. pneumoniae involved in antibiotic resistance. This result opens up megahertz serial femtosecond crystallography (SFX) as a tool for reliable structure determination, substrate screening and the efficient measurement of the evolution and dynamics of molecular structures using megahertz repetition rate pulses available at this new class of X-ray laser source

    MHC-correlated preferences in diestrous female horses (Equus caballus).

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    Genes of the major histocompatibility complex (MHC) have been shown to influence communication in many vertebrates, possibly with context-specific MHC-correlated reactions. Here we test for MHC-linked female preferences in the polygynous horse (Equus caballus) by repeatedly exposing 19 mares to a group of seven sexually experienced stallions. Each mare was tested four times during two consecutive reproductive cycles, twice during estrus and twice during diestrus. Male plasma testosterone concentrations were determined from weekly blood samples, and equine leukocyte antigen (ELA) class I and II alleles were determined serologically at the end of the experiments. Perception of male attractiveness was strongly dependent on estrous cycle: mean preference scores did not correlate for mares in diestrus and estrus and varied more during estrus than during diestrus. We found elevated female interests for MHC-dissimilar stallions, but only during diestrus, not during estrus. Female preferences were not significantly predicted by mean male testosterone plasma concentrations. However, testosterone concentrations changed during the 11 weeks of the experiment. By the end of the experiment, average testosterone concentration was significantly correlated to the average number of MHC alleles the stallions shared with the mares. We conclude that the MHC affects female preferences for stallions, but non-MHC linked male characteristics can overshadow effects of the MHC during estrus

    Climate, soil and land-use based land suitability evaluation for oil palm production in Ghana

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    In the past decade, oil palm (Elaeis guineensis Jacq.) has become the world’s most important oil crop. The large demand for palm oil has resulted in a rapid expansion of oil palm cultivation across the globe. Because of the dwindling availability of land in Southeast Asia, most expansion of the industry is expected in Central and South America and sub-Saharan Africa, where land with suitable agro-ecological conditions is available. Using Ghana as a case study, a method for evaluating areas that are both suitable and available for oil palm production is presented. Our assessment used spatial data and GIS techniques, and showed that areas with suitable climatic conditions (annual average water deficit <400 mm) is about 20% greater than was previously identified. The observed differences are the result of using different methods to determine suitability, and climate change. A major climatic factor limiting suitability for oil palm production in Ghana is the annual water deficit, with the most suitable areas located in the rainforest and semi-deciduous forest zones with higher rainfall in southern Ghana. Opportunities for large-scale oil palm plantation development is limited, however, because of the lack of availability of large and contiguous tracts of land that are required for commercial plantation oil palm development. A feasible strategy for oil palm expansion is therefore smallholder production, which can make use of smaller parcels of land. Alternatively, oil palm production in Ghana can be increased by yield intensification on land already planted to oil palm. This can also reduce the requirement for further land clearance for new plantations to meet the growing demand for palm oil. Such assessments will be essential for guiding government policy makers and investors considering investments in oil palm development

    Adapting oil palm best management practices to Ghana: opportunities for production intensification.

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    Smaller yields in Western Australia (WA), Australia, are partly the result of sub-optimal climate conditions and poor management practices. Water stress is the main yield-determining factor outside management control in WA. In order to guide government policy makers and investors, it is essential to know where the most suitable conditions for the expansion of oil palm production in WA exists. Using Ghana as a case study, this paper describes a framework for evaluating areas that are both suitable and available for oil palm production based upon land suitability evaluation methods and geographical information system techniques. The suitability assessment shows that highly fragmented suitable areas for oil palm production in Ghana are limiting the expansion of large-scale plantings. Therefore, a feasible strategy for expansion of smallholder production is needed, provided there are enough and efficient milling facilities to process the fruit. Some recommendations are given for sustainable development of the oil palm sector in Ghana

    Simulating potential growth and yield of oil palm (Elaeis guineensis) with PALMSIM: Model description, evaluation and application.

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    Reducing the gap between water-limited potential yield and actual yield in oil palm production systems through intensification is seen as an important option for sustainably increasing palm oil production. Simulation models can play an important role in quantifying water-limited potential yield, and therefore the scope for intensification, but no oil palm model exists that is both simple enough and at the same time incorporates sufficient plant physiological knowledge to be generally applicable across sites with different growing conditions. The objectives of this study therefore were to develop a model (PALMSIM) that simulates, on a monthly time step, the potential growth of oil palm as determined by solar radiation and to evaluate model performance against measured oil palm yields under optimal water and nutrient management for a range of sites across Indonesia and Malaysia. The maximum observed yield in the field matches the corresponding simulated yield for dry bunch weight with a RMSE of 1.7 Mg ha?1 year?1 against an observed yield of 18.8 Mg ha?1. Sensitivity analysis showed that PALMSIM is robust: simulated changes in yield caused by modifying the parameters by 10% are comparable to other tree crop model evaluations. While we acknowledge that, depending on the soils and climatic environment, yields may be often water limited, we suggest a relatively simple physiological approach to simulate potential yield, which can be usefully applied to high rainfall environments and is considered as a first step in developing an oil palm model that also simulates water-limited potential yield. To illustrate the application possibil- ities of the model, PALMSIM was used to create a potential yield map for Indonesia and Malaysia by sim- ulating the growth and yield at a resolution of 0.1?. This map of potential yield is considered as a first step towards a decision support tool that can identify potentially productive, but at the moment degraded sites in Indonesia and Malaysia.

    Benchmarking Yield for Sustainable Intensification of Oil Palm Production in Indonesia using PALMSIM

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    The physiological oil palm growth model PALMSIM can be used to estimate yield ceilings that provide benchmarks for sustainable intensification of oil palm production, either by expansion of cultivation to degraded sites or by increasing production from areas under cultivation. This is demonstrated using two case studies. In the first case study, PALMSIM estimates of water-limited yield for Kalimantan was overlaid onto a recently published map showing degraded sites potentially suitable for oil palm cultivation. A large proportion (35.6%; or 115,300 km2) of the identified areas fell into the potential productivity range of 35 to 40 tonnes FFB per hectare. In the second case study, PALMSIM was used to estimate potential yield for six plantation sites in Indonesia where best management practices (BMP) were assessed for yield intensification by the International Plant Nutrition Institute (IPNI) Southeast Asia Program (SEAP) and its collaborating plantation partners. Potential yields are generally higher in Sumatra than in Kalimantan due to higher solar radiation. Water deficit was a problem at two sites. The gap between water-limited yield and actual yield differs from location to location, and therefore requires a site-specific analysis. In these two case studies, the scope for sustainable intensification at regional and at plantation level was explored in a quantitative manner - a novel approach to oil palm production

    On the use of multilayer Laue lenses with X-ray Free Electron Lasers

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    Multilayer Laue lenses were used for the first time to focus x-rays from an X-ray Free Electron Laser (XFEL). In an experiment, which was performed at the European XFEL, we demonstrated focusing to a spot size of a few tens of nanometers. A series of runs in which the number of pulses per train was increased from 1 to 2, 3, 4, 5, 6, 7, 10, 20 and 30 pulses per train, all with a pulse separation of 3.55 us, was done using the same set of lenses. The increase in the number of pulses per train was accompanied with an increase of x-ray intensity (transmission) from 9% to 92% at 5 pulses per train, and then the transmission was reduced to 23.5 % when the pulses were increased further. The final working condition was 30 pulses per train and 23.5% transmission. Only at this condition we saw that the diffraction efficiency of the MLLs changed over the course of a pulse train, and this variation was reproducible from train to train. We present the procedure to align and characterize these lenses and discuss challenges working with the pulse trains from this unique x-ray source

    Livestock solutions to regenerate soils and landscapes for sustainable agri-food systems transformation in Africa

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    Agri-food systems approaches have gained international recognition over the last years. The role of livestock—both in mixed crop-livestock and pastoral systems—in sustainable agri-food systems transformation remains contested. In this review paper we present new analyses of original data from an international livestock expert survey, a quantitative search in Web of Science, and a literature review to unravel the potential for livestock systems to sustainably transform agri-food systems through regenerating soils and restoring degraded landscapes. We (i) illustrate how livestock is important for people and planet alike; (ii) review how to harness livestock's potential for rehabilitation of soils and landscapes; (iii) demonstrate successful case studies of livestock solutions such as improved forages for cut-and-carry systems and grazing management; and (iv) identify four critical steps required for lasting change at continental scale. We conclude that livestock solutions can be key catalysts for sustainable agri-food systems transformation that merit accelerated public and private investments. More research is needed to develop concrete, operational and practical livestock solutions, and measure, monitor and report their contributions and progress toward the 2030 Agenda for Sustainable Development
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