310 research outputs found

    Evaluation of innovative products to reduce copper applications to control potato late blight in organic production systems

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    The main objective of this project, VETAB project, is to determine alternatives to massive copper utilization to control potato late blight (Phytophtora infestans (Mont.) de Bary) in organic systems. To reach such a target, we first performed a screening of candidate products and additives based on their efficiency in the laboratory, under controlled conditions. We evaluated a wide range of products: formulations with a low level of copper, antagonists suspensions, aminoacid extracts, plants extracts, potassium salts, sulphur formulation, organically stabilised peroxide and rhamnolipids. The product's suspensions were applied by vaporization on potato plants. Two different protocols of application were elaborated. To test the fungicide protection action, the product was applied four days before inoculation of the pathogen. To evaluate the defence stimulating effect, the product was applied several times during the plant growth before inoculation of the pathogen. The last vaporization was performed 4 days before inoculation. We also evaluated the resistance of the product to washing risk. Pathogen suspension was applied as droplets of 5 x 10(4) spo/ml on detached leaves. The leaves were then incubated (18 degrees C, RH > 90%, 6 days) in order to record symptoms development. The best results were obtained with formulations integrating reduced doses of copper and with potassium salts. In conclusion, a wide range of products and additives are proposed on the market but very few of those have a real efficiency. The performance of the most efficient products has to be confirmed in field trials

    Multilocal field trials to test alternative products to reduce copper applications to control potato late blight in organic systems

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    The main objective of those trials was to determine alternatives to massive copper utilization to control potato late blight (Phytophthora infestans (Mont.) de Bary) in organic systems. To reach such a target, we first performed a screening of candidates products and additives under controlled conditions in the laboratory. Thereafter, the most promising products were tested in the field in 2006. Those trials were set up in three different sites, two sites in Belgium and one site in France. Herseaux (B) and Loos-en-Gohelle (F) are situated near by see level in an important potato culture basin with silty soil. Libramont is located at 500 m of altitude, far from any potato culture basin, with a sandy-loamy and stony soil. The cultivar Ditta was used in Belgium while the cultivar Juliette was planted in France. Their resistance to foliage late blight is, respectively, medium and medium-high. In total 8 modalities were compared. The products were applied in accordance to the advice of the local late blight warning system. The control was sprayed, at each advice, with 3 kg/ha of copper sulphate (Bordeaux mixture). We tested two additives to Bordeaux mixture, used at the 3 kg/ha rate as well, the first one is a short chain amino-acid extract, used to enhance rainfastness, while the other one is an hydrogen peroxide stabilised with an organic molecule. This second product was used for its disinfectant effect added to the protection effect of copper sulphate. We also tested the efficiency of a formulation presenting a low copper concentration (Glutex CU 90 with 10% copper) and of an association between a potassium phosphite and a copper tallate (Solucuivre with 5% copper). Those two components were also evaluated separately. Finally, we tested a product containing rhamnolipid biosurfactant (Zonix) supposed to physically destroy the zoospore's membrane. The 2006 climatic conditions were very particular. June and July were very dry while August was very wet with optimum late blight development conditions. The disease development was very slow during July and radically increased during August

    Do people have insight into their face recognition abilities?

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    Diagnosis of developmental or congenital prosopagnosia (CP) involves self-report of everyday face recognition difficulties, which are corroborated with poor performance on behavioural tests. This approach requires accurate self-evaluation. We examine the extent to which typical adults have insight into their face recognition abilities across four studies involving nearly 300 participants. The studies used five tests of face recognition ability: two that tap into the ability to learn and recognise previously unfamiliar faces (the Cambridge Face Memory Test, CFMT, Duchaine & Nakayama, 2006 and a newly devised test based on the CFMT but where the study phases involve watching short movies rather than viewing static faces – the CFMT-Films) and three that tap face matching (Benton Facial Recognition Test, BFRT, Benton, Sivan, Hamsher, Varney, & Spreen, 1983; and two recently devised sequential face matching tests). Self-reported ability was measured with the 15-item Kennerknecht et al. (2008) questionnaire; two single-item questions assessing face recognition ability; and a new 77-item meta-cognition questionnaire). Overall, we find that adults with typical face recognition abilities have only modest insight into their ability to recognise faces on behavioural tests. In a fifth study, we assess self-reported face recognition ability in people with CP and find that some people who expect to perform poorly on behavioural tests of face recognition do indeed perform poorly. However, it is not yet clear whether individuals within this group of poor performers have greater levels of insight (i.e., into their degree of impairment) than those with more typical levels of performance

    Identifying Hallmark Symptoms of Developmental Prosopagnosia for Non-Experts

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    Developmental prosopagnosia (DP) is characterised by a severe and relatively selective deficit in face recognition, in the absence of neurological injury. Because public and professional awareness of DP is low, many adults and children are not identified for formal testing. This may partly result from the lack of appropriate screening tools that can be used by non-experts in either professional or personal settings. To address this issue, the current study sought to (a) explore when DP can first be detected in oneself and another, and (b) identify a list of the condition’s everyday behavioural manifestations. Questionnaires and interviews were administered to large samples of adult DPs, their unaffected significant others, and parents of children with the condition; and data were analysed using inductive content analysis. It was found that DPs have limited insight into their difficulties, with most only achieving realisation in adulthood. Nevertheless, the DPs’ reflections on their childhood experiences, together with the parental responses, revealed specific indicators that can potentially be used to spot the condition in early childhood. These everyday hallmark symptoms may aid the detection of individuals who would benefit from objective testing, in oneself (in adults) or another person (for both adults and children)

    Mutations in KEOPS-Complex Genes Cause Nephrotic Syndrome with Primary Microcephaly

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    Galloway-Mowat syndrome (GAMOS) is an autosomal-recessive disease characterized by the combination of early-onset nephrotic syndrome (SRNS) and microcephaly with brain anomalies. Here we identified recessive mutations in OSGEP, TP53RK, TPRKB, and LAGE3, genes encoding the four subunits of the KEOPS complex, in 37 individuals from 32 families with GAMOS. CRISPR-Cas9 knockout in zebrafish and mice recapitulated the human phenotype of primary microcephaly and resulted in early lethality. Knockdown of OSGEP, TP53RK, or TPRKB inhibited cell proliferation, which human mutations did not rescue. Furthermore, knockdown of these genes impaired protein translation, caused endoplasmic reticulum stress, activated DNA-damage-response signaling, and ultimately induced apoptosis. Knockdown of OSGEP or TP53RK induced defects in the actin cytoskeleton and decreased the migration rate of human podocytes, an established intermediate phenotype of SRNS. We thus identified four new monogenic causes of GAMOS, describe a link between KEOPS function and human disease, and delineate potential pathogenic mechanisms

    Cent scientifiques répliquent à SEA (Suppression des Expériences sur l’Animal vivant) et dénoncent sa désinformation

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    La lutte contre la maltraitance animale est sans conteste une cause moralement juste. Mais elle ne justifie en rien la désinformation à laquelle certaines associations qui s’en réclament ont recours pour remettre en question l’usage de l’expérimentation animale en recherche
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