506 research outputs found

    Professional training and participatory research: Combined actions for developing organic rice farming in the Camargue region of France

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    In 2006 and 2007, INRA’s Joint Research Unit, Innovation, was a partner in a European professional training project within the framework of the Leonardo da Vinci programme. The objective of this project was to help develop organic rice farming in the major European rice-growing regions where rice is mainly cultivated in ecologically-sensitive areas. In France, the rate of conversion to organic production is much lower that what would be expected, since organic rice farming presents particular technical problems. The availability of expert support is critical to successful conversion and no structured training was available in the past. This is the reason why we developed a participatory training method that helps rice growers and stakeholders to convert to organic farming and to improve their organic rice production. Different training sessions were organised. The participants shared their thoughts about technical problems encountered and identified possible solutions. Some of the topics developed were weeds, soils and fertility, and varieties. At the end of these sessions, a motivated workgroup was set up. Some of its members even proposed to assess the efficiency of some of the techniques that were discussed during the work sessions in fields on their own farms. Furthermore, field visits were organised in the Camargue region of France and in Spain. Scientists and group members hope to be able to continue to work together after the O.R.P.E.S.A. project is over. In order to make this possible, we are now planning to initiate new research and development actions using the same approach

    Novelty Search in Competitive Coevolution

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    One of the main motivations for the use of competitive coevolution systems is their ability to capitalise on arms races between competing species to evolve increasingly sophisticated solutions. Such arms races can, however, be hard to sustain, and it has been shown that the competing species often converge prematurely to certain classes of behaviours. In this paper, we investigate if and how novelty search, an evolutionary technique driven by behavioural novelty, can overcome convergence in coevolution. We propose three methods for applying novelty search to coevolutionary systems with two species: (i) score both populations according to behavioural novelty; (ii) score one population according to novelty, and the other according to fitness; and (iii) score both populations with a combination of novelty and fitness. We evaluate the methods in a predator-prey pursuit task. Our results show that novelty-based approaches can evolve a significantly more diverse set of solutions, when compared to traditional fitness-based coevolution.Comment: To appear in 13th International Conference on Parallel Problem Solving from Nature (PPSN 2014

    Premiers essais de comportement de quelques espèces d'Acacias gommiers australiens en Corse du sud

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    Une expérimentation a été menée en Corse du sud, de 1983 à 1986 afin de tester les capacités de croissance et production gommière d une vingtaine d espèces d Acacias australiens (1 500 individus environ). La moitié d entre elles ont produit de la gomme en plus ou moins grande quantité. Parmi les 7 espèces plus particulièrement retenues, l Acacia mearnsii s est révélé très remarquable par la qualité de sa gomme proche de celle du meilleur gommier saharien, Acacia senegal

    French lag in scientific research on organic farming: a scientometric approach

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    France suffers from a large research deficit in most areas related to sustainable development and public health. The case of research on organic farming, within the framework of the broader sector of agronomic research, constitutes a largely under-investigated field. Even if the demand for organic products is rapidly growing in Europe, research in this field still suffers from a lack of funding and researchers. A bibliometric analysis based on key words from scientific publications (in English only) taken from Thomson Scientific’s ISI Web of Science reference database made it possible to determine sufficiently relevant indicators for a comparison of national research efforts from 2000-2006, and to therefore assess actual research priorities in the area of organic farming. Beyond traditional specialisation analyses, the ratio between the world share of publications of a given country in organic farming and its world share of publications in specific disciplines and sub-disciplines (according to the nomenclature of the French Observatory for Sciences and Techniques) allowed us to obtain these prioritisation indexes that act as policy and priority (or prioritisation activity) indicators for research institutions involved in the concerned area. An index above 1 indicates an over-specialisation, whereas an index below 1 indicates an under-specialisation. For the period 2000-2006, the European Union obtained a specialisation index of 1.52 in the area of organic farming, compared to 0.68 for the US, 0.98 for Brazil and 0.18 for China. However, this seemingly satisfactory average for Europe as a whole hides important disparities between European countries. Moreover, France is at the very end of the classification for all indexes with only 0.47 specialisation, compared to Germany with 1.19, Italy with 1.39, Austria with 2.78, Sweden with 3.99, Finland with 4.46 and Denmark with 12.19. The prioritisation index for organic farming in comparison to the discipline, “Applied biology and ecology”, is 1.65 for the EU27, 0.69 for the US, 1.7 for Germany, 3.98 for Austria, 3.84 for Finland, 9.45 for Denmark and 0.49 for France. In comparison to the subdiscipline, “Agriculture, plant biology” the index is 1.5 for the EU27, 0.98 for the US, 1.61 for Germany, 3.28 for Austria, 1.52 for Finland, 9.79 for Denmark, and 0.41 for France. Finally, for the sub-discipline, “Agro-food”, it is 1.86 for the EU27, 0.73 for the US, 1.98 for Germany, 6.92 for Austria, 7.39 for Finland, 9.39 for Denmark and 0.58 for France. These results confirm that research on organic farming is largely under-prioritised in France. The French national research effort is therefore far from meeting the ecological and economic challenges facing agriculture in the 21st century

    Establishing references to optimise organic fertilisation in organic rice farming in the Camargue region of France

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    The mineralization rate of a commercial organic fertiliser was evaluated over the course of three years in an organic rice field in the Camargue (France). The effect of different mounts of fertiliser applied at different periods was tested. The organic fertiliser rapidly mineralised under flooded conditions. On the basis of this result, we demonstrated that an adaptation of organic fertilisation practices, similar to those employed for mineral fertilisers, would result in the optimisation of organic fertilisers, leading to improved profitability

    Broadband terahertz heterodyne spectrometer exploiting synchrotron radiation at megahertz resolution

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    International audienceA new spectrometer allowing both high resolution and broadband coverage in the terahertz (THz) domain is proposed. This instrument exploits the heterodyne technique between broadband synchrotron radiation and a quantum cascade laser (QCL) based molecular THz laser that acts as the local oscillator (LO). Proof of principle for exploitation for spectroscopy is provided by the recording of molecular absorptions of hydrogen sulfide (H 2 S) and methanol (CH 3 OH) around 1.073 THz. Ultimately, the spectrometer will enable to cover the 1-4 THz region in 5 GHz windows at Doppler resolution

    A spectral line shape analysis of motional stark effect spectra

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    12th International Congress on Plasma Physics, 25-29 October 2004, Nice (France)Recent observations of MSE spectra carried out on Tore-Supra show discrepancies between experimental and theoretical intensities calculated at equilibrium. We present here a kinetic model, based on the selectivity of excitation cross sections of Stark states in the parabolic basis. Redistribution due to ion-atom collisions among Stark states of level n=3 allow to calculate the population of Stark states. This model permits to improve significantly the agreement between measured and calculated MSE spectra

    DNA Dosimetry Assessment for Sunscreen Genotoxic Photoprotection

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    Background: Due to the increase of solar ultraviolet radiation (UV) incidence over the last few decades, the use of sunscreen has been widely adopted for skin protection. However, considering the high efficiency of sunlight-induced DNA lesions, it is critical to improve upon the current approaches that are used to evaluate protection factors. An alternative approach to evaluate the photoprotection provided by sunscreens against daily UV radiation-induced DNA damage is provided by the systematic use of a DNA dosimeter. Methodology/Principal Findings: The Sun Protection Factor for DNA (DNA-SPF) is calculated by using specific DNA repair enzymes, and it is defined as the capacity for inhibiting the generation of cyclobutane pyrimidine dimers (CPD) and oxidised DNA bases compared with unprotected control samples. Five different commercial brands of sunscreen were initially evaluated, and further studies extended the analysis to include 17 other products representing various formulations and Sun Protection Factors (SPF). Overall, all of the commercial brands of SPF 30 sunscreens provided sufficient protection against simulated sunlight genotoxicity. In addition, this DNA biosensor was useful for rapidly screening the biological protection properties of the various sunscreen formulations. Conclusions/Significance: The application of the DNA dosimeter is demonstrated as an alternative, complementary, and reliable method for the quantification of sunscreen photoprotection at the level of DNA damage.Natura Inovacao e Tecnologia de Produtos LTDA (Sao Paulo, Brazil)Natura Inovacao e Tecnologia de Produtos LTDA (Sao Paulo, Brazil)FAPESP (Sao Paulo, Brazil)FAPESP (Sao Paulo, Brazil)CNPq (Brasilia, Brazil)CNPq (Brasilia, Brazil)Natura Inovacao e Tecnologia de Produtos LTDANatura Inovacao e Tecnologia de Produtos LTD

    Local adaptations of Mediterranean sheep and goats through an integrative approach

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    Small ruminants are suited to a wide variety of habitats and thus represent promising study models for identifying genes underlying adaptations. Here, we considered local Mediterranean breeds of goats (n = 17) and sheep (n = 25) from Italy, France and Spain. Based on historical archives, we selected the breeds potentially most linked to a territory and defined their original cradle (i.e., the geographical area in which the breed has emerged), including transhumant pastoral areas. We then used the programs PCAdapt and LFMM to identify signatures of artificial and environmental selection. Considering cradles instead of current GPS coordinates resulted in a greater number of signatures identified by the LFMM analysis. The results, combined with a systematic literature review, revealed a set of genes with potentially key adaptive roles in relation to the gradient of aridity and altitude. Some of these genes have been previously implicated in lipid metabolism (SUCLG2, BMP2), hypoxia stress/lung function (BMPR2), seasonal patterns (SOX2, DPH6) or neuronal function (TRPC4, TRPC6). Selection signatures involving the PCDH9 and KLH1 genes, as well as NBEA/NBEAL1, were identified in both species and thus could play an important adaptive role
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