Abstract
High-resolution electron microscopy (HREM) studies of the microstructure andspecific defects in hexagonal boron nitride (h-BN) precursors and cubic boronnitride (c-BN) crystals made under high-pressure high-temperature conditionsrevealed the presence of half-nanotubes at the edges of the h-BN particles. Theirsp3 bonding tendency could strongly influence the nucleation rates of c-BN. Theatomic resolution at extended dislocations was insufficient to allow us to determinethe stacking fault energy in the c-BN crystals. Its mean value of 191 ± 15 mJm−2 is of the same order of magnitude as that of diamond. High-frequency (94GHz) electron paramagnetic resonance studies on c-BN single crystals haveproduced new data on the D1 centres associated with the boron species.Ion-beam-induced luminescence measurements have indicated that c-BN is a veryinteresting luminescent material, which is characterized by four luminescencebands and exhibits a better resistance to ionizing radiation than CVD diamond.
Highlights
The incidence of invasive meningococcal disease (IMD), caused by Neisseria meningitidis, is low in Europe, but case fatality is high (0.8 cases/100,000 inhabitants and 8.7%, resp., in 2011) [1]
The consortium defined research questions for guidance focused on the prevention of subsequent cases following sporadic cases of IMD and based on the needs identified through two previous surveys among public health representatives of EU countries [6, 18]
In 2013, we evaluated the impact of this guidance on the recommendations for public health management of IMD in European countries and found out that 90% of the 31 EU countries or regions found it useful at the national level and that 50% used it to update their national guidelines within the three years following the publication of the guidance [32]
Summary
The incidence of invasive meningococcal disease (IMD), caused by Neisseria meningitidis, is low in Europe, but case fatality is high (0.8 cases/100,000 inhabitants and 8.7%, resp., in 2011) [1]. Information often comes from observational studies that are more prone to bias and are considered to provide a lower quality of evidence [10] Such studies can still be used in developing recommendations if systematically researched and graded appropriately [11]. We share our experience and lessons learned in using different types and quality of evidence to develop guidance on the public health management of IMD for European countries within a short time period using GRADE methodology. The aim of this guidance, available on the ECDC website, was to assist countries across Europe in making decisions about appropriate measures to control and prevent IMD in contacts of cases at national and subnational levels [12]
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