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OBJECTIVES: To investigate time patterns of compliance with nutrient goals recommended by the World Health Organization (WHO). DESIGN: A single aggregated indicator of distance from the key WHO recommendations for a healthy diet is built using FAOSTAT intake data, bounded between 0 (maximum possible distance from goals) and 1 (perfect adherence). Two hypotheses are tested for different country groupings: (1) whether adherence has improved over time; and (2) whether cross-country disparities in terms of diet healthiness have decreased. SETTING: One hundred and forty-nine countries, including 26 countries belonging to the Organisation for Economic Co-operation and Development (OECD) and 115 developing countries (including 43 least developed countries), with yearly data over the period 1961-2002. RESULTS: The Recommendation Compliance Index (RCI) shows significant improvements in adherence to WHO goals for both developing and especially OECD countries. The latter group of countries show the highest levels of the RCI and the largest increase over time, especially between 1981 and 2002. No improvement is detected for least developed countries. A reduction in disparities (convergence of the RCI) is observed only within the OECD grouping. CONCLUSIONS: Adherence to healthy eating guidelines depends on economic development. Diets are improving and converging in advanced economies, but developing and especially least developed countries are still far from meeting WHO nutrition goals. This confirms findings on the double burden of malnutrition and suggests that economic drivers are more relevant than socio-cultural factors in determining the healthiness of diets.  相似文献   
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Standard area diagrams (SADs) to assess the severity of potato early blight (Alternaria grandis) on leaves of potato (Solanum tuberosum L.) were developed and validated. The proposed SADs include images of leaves with 10 distinct disease severities (0.1, 1, 3, 5, 10, 20, 40, 60, 80 and 100 %). The SADs were validated by 12 raters who had no previous experience in evaluating plant disease. Lin’s concordance correlation analysis of estimated vs. actual disease severity (based on image analysis) showed that precision and accuracy improved for most raters using the SADs, compared to assessments made without the SADs. The SADs improved accuracy (coefficient of bias, C b ?=?0.97 and 0.99, without and with SADs, respectively) and agreement (Lin’s concordance correlation coefficient, ρ c ?=?0.91 and 0.98 without and with SADs, respectively) of the estimates of severity. Severity estimates were more reliable when using SADs (coefficient of determination, R 2 ?=?0.80 unaided and R 2 ?=?0.95 with SADs, and the intra-class correlation ρ?=?0.86 without SADs and ρ?=?0.97 using the SADs). The SADs improved raters’ ability to accurately, precisely and reliably estimate potato early blight severity, and as such can be used to assess severity for several purposes, including breeding for resistance, fungicide screening, and pathotype characterization.  相似文献   
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We investigated the dynamics of porcine reproductive and respiratory syndrome virus (PRRSV) variability in a range of swine PRRS-positive farms located in Northern Italy, to provide insights into the epidemiology and diffusion of the virus, particularly throughout the entire swine production chain. In this context, we also examined the effectiveness and the critical points of a recently developed gilts acclimatization program in swine breeder farms. To achieve these aims, we designed new primers and determined 64 complete open reading frame 5 (ORF5) sequences, representing Italian PRRSV field strains and the European vaccine Porcilis strain (Intervet); in addition, the more conserved ORF7 of 11 PRRSV strains were sequenced. The domains' prediction of their putative protein sequences was performed as well. Based on these sequences, phylogenetic trees were inferred which revealed a high degree of variability among the PRRSV Italian strains. The outcomes of the phylogenetic analysis showed that the most frequent source of infection in PRRS-positive farms (sow herds, nursery sites, fattening units) was the introduction of animals carrying a new variant and not the modification of already present variants; moreover, the integration of data from phylogenetic analysis and from the clinical and serological status of the swine herds suggested that the acclimatization program could be a valid tool to stabilize the PRRS clinical picture in farms, only when applied in combination with rigorous bio-security routine management and avoid the incoming of new PRRSV variants.  相似文献   
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