814 research outputs found

    Diverse strategies for copper production in Chalcolithic Iberia

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    Our understanding of early copper metallurgy in the Iberian Peninsula is mostly based on analysis from well-studied regions in the Southeast and Southwest. This paper focuses on two recently recovered Chalcolithic metallurgical assemblages outside these traditional research foci: two slagged crucibles from Lugar Viejo III (Zaragoza) and two large slag cakes from Cueva del Cañaveralejo (Córdoba). Analysis of the compositions and microstructures of the artifacts using optical microscopy and scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS) suggests they are related to primary copper production, namely smelting in crucible-furnaces under relatively oxidizing conditions, as is standard for this period. The slag layers on crucibles from Lugar Viejo indicate the production of copper with minor amounts of arsenic, also typical for this period. Of special note is the use of organic temper in the crucibles from Lugar Viejo, a practice found at the nearby site of Moncín but rare at other sites in Iberia. However, the slags from Cueva del Cañaveralejo are atypical in their large size (approx. 125 g each), fayalitic composition, unusual efficiency as demonstrated by a low copper content, and lack of arsenic; furthermore, the high sulfur content raises the possibility of the use of sulfidic ores. Results from both sites are compared against published data from well-known sites such as Los Millares, Las Pilas, Almizaraque, and Bauma del Serrat del Pont. The new data from Lugar Viejo and Cueva del Cañaveralejo reinforce the interpretation of metallurgy in the Iberian Peninsula as a low-skilled, conservative technology but also indicate the need for more research into regional variations. (See Supplementary Data 1 for a summary in Spanish)

    Clinical trials in a remote Aboriginal setting: lessons from the BOABS smoking cessation study

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    Background: There is limited evidence regarding the best approaches to helping Indigenous Australians to stop smoking. The composite analysis of the only two smoking cessation randomised controlled trials (RCTs)investigating this suggests that one-on-one extra support delivered by and provided to Indigenous Australians in a primary health care setting appears to be more effective than usual care in encouraging smoking cessation. This paper describes the lessons learnt from one of these studies, the Be Our Ally Beat Smoking (BOABS) Study, and how to develop and implement an integrated smoking cessation program. Methods: Qualitative study using data collected from multiple documentary sources related to the BOABS Study. As the project neared completion the research team participated in four workshops to review and conduct thematic analyses of these documents. Results: Challenges we encountered during the relatively complex BOABS Study included recruiting sufficient number of participants; managing the project in two distant locations and ensuring high quality work across both sites; providing appropriate training and support to Aboriginal researchers; significant staff absences, staff shortages and high workforce turnover; determining where and how the project fitted in the clinics and consequent siloing of the Aboriginal researchers relating to the requirements of RCTs; resistance to change, and maintaining organisational commitment and priority for the project.The results of this study also demonstrated the importance of local Aboriginal ownership, commitment, participation and control. This included knowledge of local communities, the flexibility to adapt interventions to local settings and circumstances, and taking sufficient time to allow this to occur. Conclusions: The keys to the success of the BOABS Study were local development, ownership and participation, worker professional development and support, and operating within a framework of cultural safety. There were difficulties associated with the BOABS Study being an RCT, and many of these are shared with stand-alone programs. Interventions targeted at particular health problems are best integrated with usual primary health care. Research to investigate complex interventions in Indigenous health should not be limited to randomised clinical trials and funding needs to reflect the additional, but necessary, cost of providing for local control of planning and implementation

    Ganhos genéticos para caracteres de raiz em populações de cenoura nos sistemas orgânico e convencional de produção

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    O objetivo deste trabalho foi verificar os ganhos genéticos para caracteres de raiz em populações de cenoura cultivadas nos sistemas orgânico e convencional. Os experimentos foram conduzidos na Embrapa Hortaliças, Brasília (DF). Duas populações de cenoura derivadas da cultivar Brasília e de origem comum até 2002, foram subdivididas em duas populações, avaliadas e selecionadas, por oito gerações consecutivas, nos verões de 2000 a 2007. Em 2008, amostras de sementes das populações, provenientes de cada ciclo de seleção, foram semeadas em campo e conduzidas sob manejo orgânico e convencional de produção, em delineamento de blocos casualizados com nove tratamentos, quatro repetições e parcelas de 1 m². Aos 90 dias após a semeadura, 20 raízes por parcela foram colhidas para a avaliação dos caracteres comprimento, diâmetro do xilema e do floema; comprimento da extensão do ombro verde; massa fresca; presença de halo; formato de ponta e de ombro e coloração do xilema e floema. Foi realizada análise de variância com determinação da interação entre tratamentos e sistemas de produção, agrupamento de médias entre os tratamentos, e calculados os ganhos reais com a seleção. Pôde-se verificar que nos oito anos de seleção não houve ganhos significativos para os caracteres estudados nas duas populações. Com isso, conclui-se que os caracteres avaliados já se encontram fixados nas duas populações estudadas. Verificou-se que a seleção não precisa ser realizada nos dois sistemas de cultivo, orgânico e convencional, possibilitando diminuição de recursos financeiros e de mão-de-obra empregados no melhoramento.The objective of this work was to evaluate the genetic gain with the selection of root characters of carrot populations cultivated in organic and conventional production systems. The experiments were carried out at Embrapa Hortaliças, Brasília, Brazil. Two carrot populations derived from Brasília cultivar and with common origin until 2002, were separate in two populations and evaluated for eight generations during 2000 to 2007. In 2008, seed samples of the population in each cycle of selection were sowed in the field in both organic and conventional production systems, in a randomized blocks design with four replications of nine treatments and plots of 1 m². After 90 days of sowing, 20 roots per plot were harvested for the evaluation of the length, xylem and phloem diameter, green shoulder length, fresh mass, presence of halo, tip and shoulder format, and the color parameters of xylem and phloem. Variance analysis was carried out to determine the interaction between treatments and production systems, grouping of means among treatments, and the real gain with the selection was estimated. In the last eight years of selection, a significant gain was not observed on the studied characters in the two populations. So we concluded that those traits are already quite developed and stabilized in both populations. The selection doesn't need to be accomplished in both areas of organic and conventional cultivation, making possible the decrease of financial and labor resources utilized in the breeding

    Tamanho de amostra para avaliação de caracteres de cenoura em sistemas de cultivo agroecológico.

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    O correto dimensionamento de experimentos deve ser utilizado para que se possa reduzir o erro experimental e com isso, maximizar a precisão das informações obtidas. O objetivo deste trabalho foi estimar o número mínimo de famílias e de plantas por parcela para avaliação de caracteres de raiz em uma população de cenoura cultivada em sistema agroecológico. Os ensaios foram conduzidos no verão de 2006/2007 em duas propriedades com cultivo agroecológico em Brasília: Associação Mokiti Okada, que segue modelo de Agricultura Natural em Brazlândia-DF e Núcleo Rural Taguatinga, seguindo modelo de Agricultura Orgânica em Taguatinga-DF. Foram avaliadas 100 famílias de meio-irmãos de cenoura dispostas em delineamento de blocos casualizados com duas repetições e parcelas de 1 m2. Foram colhidas 20 plantas competitivas por parcela e avaliadas individualmente para os caracteres comprimento de raiz, diâmetro da raiz, massa da raiz, diâmetro do xilema da raiz, relação diâmetro do xilema/diâmetro da raiz, tipo de ponta da raiz, tipo de ombro da raiz, parâmetro a* para os tecidos xilema e floema. Foi realizada análise de variância conjunta e para cada sistema, com informação entre e dentro de parcelas. Foram realizadas ainda análises de representatividade do número mínimo de famílias e de plantas para representar uma população de cenoura. Foi verificado que uma amostra de 18 plantas competitivas/parcela coletadas em ensaios com 2 repetições, bem como de 74 famílias, são suficientes para garantir uma adequada avaliação de famílias meio-irmãos de cenoura para os caracteres estudados

    Descent algorithm for nonsmooth stochastic multiobjective optimization

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    International audienceAn algorithm for solving the expectation formulation of stochastic nonsmooth multiobjective optimization problems is proposed. The proposed method is an extension of the classical stochastic gradient algorithm to multi-objective optimization using the properties of a common descent vector defined 10 in the deterministic context. The mean square and the almost sure convergence of the algorithm are proven. The algorithm efficiency is illustrated and assessed on an academic example

    A canonical correlation analysis of the association between carcass and ham traits in pigs used to produce dry-cured ham

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    The association between carcass and ham traits in a pig population used to produce dry-cured ham was studied using canonical correlation analysis. The carcass traits examined were hot carcass weight (HCW), backfat thickness (BT) and loin depth (LD), and the ham traits studied were gross ham weight (GHW), trimmed ham weight (THW), ham inner layer fat thickness (HIFT), ham outer layer fat thickness (HOFT), pH (pH) and the Göfo value. Carcass and ham traits are not independent. The canonical correlations (r) between the carcass and ham traits at 130 kg were 0.77, 0.24 and 0.20 for the first, second and third canonical pair, respectively, and were all significant (p < 0.01) by the Wilks test. The corresponding canonical correlations between the three canonical variate pairs for the carcass and ham traits at 160 kg were 0.88, 0.42 and 0.14, respectively (p < 0.05 for all, except the third). The correlations between the traits and their canonical variate showed an association among HCW, GHW and THW, and between BT and HOFT. These results indicate that carcass traits should be used to cull pigs that are not suitable for dry-cured ham production

    The nuclear envelope protein, LAP1B, is a novel protein phosphatase 1 substrate

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    Protein phosphatase 1 (PP1) binding proteins are quintessential regulators, determining substrate specificity and defining subcellular localization and activity of the latter. Here, we describe a novel PP1 binding protein, the nuclear membrane protein lamina associated polypeptide 1B (LAP1B), which interacts with the DYT1 dystonia protein torsinA. The PP1 binding domain in LAP1B was here identified as the REVRF motif at amino acids 55-59. The LAP1B:PP1 complex can be immunoprecipitated from cells in culture and rat cortex and the complex was further validated by yeast co-transformations and blot overlay assays. PP1, which is enriched in the nucleus, binds to the N-terminal nuclear domain of LAP1B, as shown by immunocolocalization and domain specific binding studies. PP1 dephosphorylates LAP1B, confirming the physiological relevance of this interaction. These findings place PP1 at a key position to participate in the pathogenesis of DYT1 dystonia and related nuclear envelope-based diseases.publishe
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