p53-dependent stimulation of redox-related genes in the lymphoid organs of γ-irradiated mice—identification of Haeme-oxygenase 1 as a direct p53 target gene

Recent data showed that p53 stimulates the expression of genes encoding not only pro- but also antioxidant enzymes. It was suggested that antioxidant genes could be induced under physiologic levels of stress while the prooxidant ones respond to higher level of stress. Results presented in this article illustrate an additional degree of complexity. We show that the expression of Haeme-oxygenase 1 (HO-1), a stress-inducible gene that codes for an enzyme having antioxidant properties, is stimulated in a p53-dependent manner in the thymus and spleen of irradiated mice. We prove that HO-1 is a direct p53 target gene by showing that the p53RE identified within human and mouse genes is specifically bound by p53. The threshold of irradiation dose required to induce a significant response of HO-1 in the lymphoid organs of the irradiated mice is higher than that for Waf1/p21 that encodes an universal inhibitor of cell cycle. Moreover, induction of HO-1 occurs later than that of Waf1/p21. Finally, the higher stimulation of HO-1 is reached when Waf1/p21 stimulation starts to decrease

Étude de l’influence de la densité de peuplement sur le fonctionnement du sol dans des chênaies par la mesuredes rapports isotopiques du carbone (13C/12C) et de l’azote (15N/14N) en EA-IRMS

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Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe

Development of an HILIC method with simultaneous ESIMS and ICPMS detection for lanthanide and actinide speciation in nuclear fuel treatment processes

Dans ce travail, des méthodes d’analyses de spéciation exhaustive de lanthanides (Ln), en présence d'acides polyaminocarboxyliques (EDTA, DTPA) utilisés comme agents de desextraction dans les procédés de traitement de combustibles nucléaires usés, ont été développées par couplage simultané HILIC-ESIMS/ICPMS. Pour réduire les volumes d’effluents chromatographiques tout en maintenant des séparations efficaces et rapides, les performances de colonnes remplies de particules entièrement poreuses (FPP) et de particules superficiellement poreuses (SPP) ont été évaluées, aboutissant à la sélection de la technologie FPP de diamètre sub-2-µm. Selon la composition des échantillons, le couplage HILIC-ESIMS peut s'avérer suffisant pour des études de spéciation exhaustive, nécessitant l'évaluation du potentiel de l'ESIMS pour la mesure de composition isotopique d'éléments. Des méthodes de mesure de rapports isotopiques du natSm complexé à l'EDTA ont alors été développées avec deux types d’ESIMS, en introduisant directement l'échantillon. Une méthode de déconvolution a ensuite été développée pour déterminer les rapports isotopiques du natSm. L'approche a été validée avec un complexe de Sm enrichi en 147Sm et 149Sm. L'étape ultérieure a consisté à déterminer les rapports isotopiques du Sm avec le couplage simultané, en appliquant plusieurs méthodes de traitements de signaux transitoires. Des méthodes de quantification par étalonnage externe et par dilution isotopique spécifique ont été ensuite développées avec ce même complexe. Les développements réalisés avec le Sm pourront être étendus à d'autres lanthanides et aux actinides.In this work, analysis methods of lanthanide (Ln) comprehensive speciation, in the presence of polyaminocarboxylic acids (EDTA, DTPA) used as back extraction agents in spent nuclear fuel treatment processes, were developed by simultaneous coupling HILIC-ESIMS/ICPMS. To reduce chromatographic effluent volumes while maintaining efficient and rapid separations, the performances of columns packed with fully porous particles (FPP) and superficially porous particles (SPP) were evaluated, resulting in the selection of the sub-2-µm FPP technology. Depending on the sample composition, HILIC-ESIMS coupling may be sufficient for comprehensive speciation studies, requiring assessment of the ESIMS potential for isotopic composition measurement of elements. The isotopic ratio measurement methods of natSm complexed with EDTA were then developed with two types of ESIMS, directly introducing the sample. A deconvolution method was then developed to determine the natSm isotope ratios. The approach was validated with Sm complex enriched in 147Sm and 149Sm. The next step was to determine the Sm isotopic ratios with the simultaneous coupling, by applying several methods of transient signal processing. Quantification methods by external calibration and specific isotopic dilution were then developed with this same complex. The developments carried out with Sm may be extended to other lanthanides and actinides

Gestion de la fertilité des sols et rôle du troupeau dans les systèmes coton-céréales-élevage au Mali-Sud (savoirs techniques locaux et pratiques d'intégration agriculture élevage)

Dans la zone Mali-Sud, l'augmentation démographique, le développement de la culture cotonnière et, parallèlement, des systèmes d'élevage ont entraîné une augmentation des surfaces cultivées, une réduction du temps de mise en jachère et un passage progressif à la culture continue. L'espace pastoral est réduit aux terres pas encore mises en culture. Dans un contexte climatique, économique et institutionnel difficile, on cherche à faire évoluer les pratiques de gestion de la fertilité des sols et d'alimentation des animaux pour renforcer les systèmes de production et ne pas hypothéquer leur durabilité. De nouvelles postures de recherche visent à transformer les situations, produire des connaissances et renforcer l'implication des acteurs. Les références élaborées par la recherche doivent être compréhensibles par l'ensemble des acteurs et prendre en compte les savoirs techniques locaux des praticiens. Cette prise en compte dans l'analyse des pratiques de gestion de la fertilité des sols permet-elle de produire des connaissances nouvelles sur les pratiques, de formuler des propositions techniques ou d'améliorer les relations recherche-vulgarisation-paysans ? Nous proposons de tester un cadre d'analyse des pratiques de gestion de fertilité des sols en nous basant sur une caractérisation préalable des savoirs techniques locaux. Ce travail est mené auprès de paysans de deux villages du Mali-Sud. La lecture des relations savoirs-pratiques permet d'apprécier la pertinence des savoirs techniques locaux, d'enrichir la description des pratiques agricoles et d'évaluer l'intérêt de cette approche pour les sciences agronomiques et pour le développement agricoleSoil fertility management and herd role in the cotton-cereals-livestock systems in south Mali, technical local knowledge and crop-livestock farming practices. In the south Mali, population growth, joint development of cotton-crop and breeding system furthered the extension of cultivated lands, furthered the development of letting fallow land for a short-lived and the extension of lands cultivated in a continuous way. The pastoral lands are limited to the none cultivated areas. In a difficult context made off climatic hazard, economic crises and institutional uncertainty, the evolution of soil fertility practices and pastoral practices is looked up to enhance the farming systems and not mortgage their sustainability. New scientific approaches aim at changing the crop and breeding systems, at producing new knowledges and at reinforcing the farmer s involvement. The technical references developed must be understandable by the farmers and the researchers and must integrate their local technical knowledges. Does the consideration of local technical knowledges in the soil fertility practices analysis enable to produce new knowledges on the practices, to elaborate technical proposals or improve the relations between researchers and farmers? We suggest to test a scientific approach to investigate soil fertility practices with the support of the characterization of the local technical knowledges. This work is performed with farmers of two villages of the South Mali. Analysis of knowledges and practices relations allows to appreciate the relevance of the local technical knowledges, allows to improve farming practices description and to assess the interest of this research method for agricultural sciences and the agricultural developmentPARIS-EST-Université (770839901) / SudocSudocFranceF

Environmental quality, public debt and economic development

Environmental quality, public debt and economic development / Mouez Fodha, Thomas Seegmulle. Greqam, janvier 2011, 24 p., document de travail n°2011-02. http://halshs.archives-ouvertes.fr/halshs-00555625/fr/ This article analyzes the consequences on capital accumulation and environmental quality of environmental policies financed by public debt. A public sector of pollution abatement is financed by a tax and/or public debt. We show that if the initial capital stock is high enough, the eco..

Étude de la spéciation exhaustive des lanthanides par couplage simultané HILIC-ESIMS/ICPMS

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Étude de la spéciation exhaustive des lanthanides et des actinides pour les procédés de traitement du combustible nucléaire : approche intégrée par spectrométries de masse

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