43 research outputs found

    Quality assessment of real-world data repositories across the data life cycle: A literature review

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    ObjectiveData quality (DQ) must be consistently defined in context. The attributes, metadata, and context of longitudinal real-world data (RWD) have not been formalized for quality improvement across the data production and curation life cycle. We sought to complete a literature review on DQ assessment frameworks, indicators and tools for research, public health, service, and quality improvement across the data life cycle.Materials and MethodsThe review followed PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Databases from health, physical and social sciences were used: Cinahl, Embase, Scopus, ProQuest, Emcare, PsycINFO, Compendex, and Inspec. Embase was used instead of PubMed (an interface to search MEDLINE) because it includes all MeSH (Medical Subject Headings) terms used and journals in MEDLINE as well as additional unique journals and conference abstracts. A combined data life cycle and quality framework guided the search of published and gray literature for DQ frameworks, indicators, and tools. At least 2 authors independently identified articles for inclusion and extracted and categorized DQ concepts and constructs. All authors discussed findings iteratively until consensus was reached.ResultsThe 120 included articles yielded concepts related to contextual (data source, custodian, and user) and technical (interoperability) factors across the data life cycle. Contextual DQ subcategories included relevance, usability, accessibility, timeliness, and trust. Well-tested computable DQ indicators and assessment tools were also found.ConclusionsA DQ assessment framework that covers intrinsic, technical, and contextual categories across the data life cycle enables assessment and management of RWD repositories to ensure fitness for purpose. Balancing security, privacy, and FAIR principles requires trust and reciprocity, transparent governance, and organizational cultures that value good documentation

    Investigation of the causes for the occurrence of residues of the anticoccidial feed additive nicarbazin in commercial poultry

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    International audienceInvestigations were undertaken to identify causes for the occurrence of high levels of the zootechnical feed additive nicarbazin in broiler liver at slaughter. The first investigation on 32 commercial broiler flocks involved sampling and analysis for nicarbazin (as dinitrocarbanilide, DNC) in liver from birds during a 3-10 day period after withdrawal of nicarbazin from their feed and prior to commercial slaughter. DNC residues in liver samples of broilers scheduled as being withdrawn from nicarbazin for ≥ 6 days ranged from 20 to > 1600 μg/kg (the specified withdrawal period for nicarbazin is 5 days and the JECFA MRL is 200 μg/kg liver). Further on-farm investigations on 12 of these flocks, selected on the basis of the feeding system in use and the levels of DNC residues determined in liver, identified issues in feed management contributing to elevated residues in broiler liver. A significant correlation (0.81, p < 0.01, n = 10) between DNC residues in liver samples and in feed samples from the feeding pans was observed. The second investigation on 12 commercial broiler flocks involved sampling and analysis for DNC in liver samples and feed samples from feeding pans and from the feed mill at the three thinnings of birds for commercial slaughter. In the case of one flock, a clear relationship between nicarbazin in feed from the feed mill (10.5 mg/kg DNC), in feed from the feeding pans (6.6 mg/kg DNC) and in liver (583 μg/kg DNC) at first thinning (9 days scheduled withdrawal from nicarbazin) was observed. Such a clear relationship was not observed in other cases, particularly at second and third thinnings, pointing to re-exposure of birds to nicarbazin late in the flock production cycle, probably from the litter. Guidelines outlining best farm practice to eliminate nicarbazin residues in poultry have been published in booklet and poster format for broiler producers and deal with feed system cleaning, feed bin management, feed deliveries, feed usage and records

    Morphology and ultrastructure of megaspores and microspores of Isoetes sehnemii Fuchs (Lycophyta)

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    The morphology and wall ultrastructure of megaspores and microspores of Isoetes sehnemii that grows in Brazil were analyzed as part of the study of the Isoetaceae present in Southern South America. The observations were performed with light, scanning and transmission electron microscopes. The megaspores are trilete, 350-450&#956;m in equatorial diameter. The surface is reticulate. In section, the sporoderm is 100&#956;m thick including the ornamentation. The wall is composed of a siliceous perispore, which consists of short fused flatten, elements forming a three-dimensional mesh. The exospore has two zones of different structure. The endospore is fibrillar. The microspores are monolete, 21-27&#956;m in equatorial diameter. The sporoderm is composed of a sporopollinic rugulate perispore. A space between the paraexospore and the exospore is evident. The exospore is compact. The endospore is fibrillar. The ultrastructural analysis akes hoologies evident concerning structure and organization of the layers belo the perispore in both spore types. A possible similarity and stability in the ultrustructure of the present spores and fossils could be also inferred. In addition, there would be a correlation among the plant habitat, the spore ornamentation and the geographic distribution.<br>A morfologia e a ultraestrutura da parede de megasporos e microspores de Isoetes sehnemii que crescem no Brasil foram analisados como parte do estudo de Isoetaceae presente no sul da América do Sul. As observações foram realizadas com microscopias de luz e eletrônicas de transmissão e varredura. Os megasporos são triletes com 350-450&#956;m de diâmetro equatorial. A superfície é reticulada. Em secção o esporoderma possui 100&#956;m de espessura incluindo ornamentação. A parede é composta de um perisporo silicoso que consiste de elementos fusionados curtos e achatados formando uma rede tridimensional. O exosporo tem duas zonas com diferentes estruturas. O endosporo é fibrilar. Os microsporos são monoletes, 21-27&#956;m de diâmetro equatorial. A esporoderme é composta por um perisporo esporopolínico rugulado. Um espaço entre o para-exosporo e o exosporo é evidente. O exosporo é compacto. O endosporo é fibrilar. A análise ultraestrutural torna evidente homologias relativas a estrutura e organização das camadas abaixo do perisporo em ambos os tipos de esporos. Uma possível similaridade e estabilidade na ultraestrutura do presente esporo e fósseis pode também ser inferida. Além disso, haveria uma correlação entre o habitat da planta, a ornamentação do esporo e a distribuição geográfica
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