We present a detailed positron 2D-ACAR measurements study of the "ridge" Fermi surface of (R)Ba_{2}Cu_{3}O_{7-δ} (R = Y, Dy) compared to full-potential linearized augmented plane wave and linear muffin-tin orbital calculations. From different 2D-ACAR projections measured in DyBa_{2}Cu_{3}O_{7-δ}, a 3D model of the momentum density of the ridge was established and is in good agreement with LMTO calculations of YΒa_{2}Cu_{3}O_{7}, confirming the description of the ridge Fermi surface by local density approximation calculations. The ridge is also studied in oxygen deficient YΒa_{2}Cu_{3}O_{7-δ}. With growing δ, the ridge disappears without changing in width. This is consistent with full-potential linearized augmented plane wave calculations of YΒa_{2}Cu_{3}O_{6.5}, and supports the phase separation model of Mesot et al.
Background: To advance human biomonitoring (HBM) for policy support in Europe, a harmonized approach was developed (COPHES project, FP7 2009- 2012) and evaluated in 17 countries (DEMOCOPHES project, Life+, 2010-2012). Cyprus (CY) and Luxembourg (LU) tested the hypothesis that the COPHES European Protocol is applicable to small countries.Materials and methods: In 2011-12, the European Protocol was adopted and tested by CY and LU for the harmonized biomonitoring of 60 children and their mothers for cadmium, phthalates and cotinine in urine and for mercury in scalp hair in two sampling areas (urban, rural). Results: Both small countries achieved the preset goals for recruitment, sample collection and analysis, which allowed for the first time the assessment of children’s and mothers’ exposures to the selected chemicals in comparison with other countries. Capacity building was accomplished and communication actions were particularly effective, with both countries taking advantage of their small size to access participants, policy makers, other stakeholders and the press. Time constrains and requirements for capacity building were limiting factors. Conclusion: The COPHES European Protocol for HBM surveys is attainable in small countries. The following elements are fundamental in the design of a harmonized European HBM program, from the perspective of small countries: (a) consultation with and active involvement of the implementing countries, (b) flexibility for national decisions, while not compromising harmonization, (c) elaboration of standardized methods, procedures and documents (d) quality assurance mechanisms, (e) means of training and support.
JavaScript is turned off in your web browser. Turn it on to take full advantage of this site, then refresh the page.