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Abstract: In this paper we report the results of the detailed monitoring and analysis of combustion emissions from fast moving diesel trains. A new highly efficient monitoring methodology is proposed based on the measurements of the total number concentration (TNC) of combustion aerosols at a fixed point (on a bridge overpassing the railway) inside the violently mixing zone created by a fast moving train. Applicability conditions for the proposed methodology are presented, discussed and linked to the formation of the stable and uniform mixing zone. In particular, it is demonstrated that if such a mixing zone is formed, the monitoring results are highly consistent, repeatable (with typically negligible statistical errors and dispersion), stable with respect to the external atmospheric turbulence and result in an unusual pattern of the aerosol evolution with two or three distinct TNC maximums. It is also shown that the stability and uniformity of the created mixing zone (as well as the repeatability of the monitoring results) increase with increasing length of the train (with an estimated critical train length of ~10 carriages, at the speed of ~150km/h). The analysis of the obtained evolutionary dependencies of aerosol TNC suggests that the major possible mechanisms responsible for the formation of the distinct concentration maximums are condensation (the second maximum) and thermal fragmentation of solid nanoparticle aggregates (third maximum). The obtained results and the new methodology will be important for monitoring and analysis of combustion emissions from fast moving trains, and for the determination of the impact of rail networks on the atmospheric environment and human exposure to combustion emissions. [ABSTRACT FROM AUTHOR]

Abstract: We investigate the effect of dissipation on adiabatic nano-focusing of surface plasmons in a sharp metal tapered rod. Three distinct patterns of nano-focusing and local field enhancement are predicted at different levels of dissipation and/or taper angles. Critical structural parameters and asymptotic behavior of the field near the tip are analyzed. [Copyright &y& Elsevier]

• Initial teacher education (ITE) influences the stability of the teaching workforce. • ITE influences beginning teachers' satisfaction with the teaching profession. • The school support beginning teachers need closely links to ITE programmes. • ITE impacts professional interrelationships with colleagues, parents and students. • Evidence links ITE to expectations and realities concerns of beginning teachers. Initial teacher education (ITE) impacts the preparedness of beginning teachers. A large scale mixed methods investigation (n = 2145) offers perceptions through surveys of beginning teachers in their first five years of teaching (n = 1362) and their school leaders (n = 736) and one-on-one semi-structured interviews (n = 47) with beginning teachers (n = 38) and school leaders (n = 9). The findings offer a deeper understanding of ITEs influence on beginning teachers' preparedness. Qualitative analysis of survey open questions and the quantitative analysis of beginning teachers (n = 504) and school leaders' (n = 306) completed Likert scale surveys items unveiled perceptions about ITEs impact on beginning teachers' satisfaction levels, expectations and realities; professional support and mentoring offered at school level; and professional interrelationships within schools. [ABSTRACT FROM AUTHOR]