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Summary: Mosquito surveillance studies to identify mosquito‐borne flaviviruses have identified West Nile Virus (WNV) for the first time in Zambia. The Zambian WNV isolate from Culex quinquefasciatus mosquitoes collected in the Western Province was closely related genetically to WNV lineage 2 South African strains which have been previously shown to be highly neuroinvasive. These data provide the first evidence of the circulation of WNV in Zambia and suggest there should be an increased awareness of possible associated human and animal diseases in that country. [ABSTRACT FROM AUTHOR]

The Cu/Sn system is one of the most fundamental and important metallic systems for solder joints in electric devices. To realize reliable solder joints, information on reactive diffusion at the solder joint is very important. In the present study, we experimentally investigated the kinetics of the reactive diffusion between solid Cu and liquid Sn using semi-infinite Cu/Sn diffusion couples prepared by an isothermal bonding technique. Isothermal annealing of the diffusion couple was conducted in the temperature range of 533-603 K for various times up to 172.8 ks (48 h). Using annealing, an intermetallic layer composed of CuSn with scallop morphology and CuSn with rather uniform thickness is formed at the original Cu/Sn interface in the diffusion couple. The growth of the CuSn scallop occurs much more quickly than that of the CuSn layer and thus predominates in the overall growth of the intermetallic layer. This tendency becomes more remarkable at lower annealing temperatures. The total thickness of the intermetallic layer is proportional to a power function of the annealing time, and the exponent of the power function is close to unity at all the annealing temperatures. This means that volume diffusion controls the intermetallic growth and the morphology of the CuSn/Sn interface influences the rate-controlling process. Adopting a mean value of 0.99 for the exponent, we obtain a value of 26 kJ/mol for the activation enthalpy of the intermetallic growth. [ABSTRACT FROM AUTHOR]

A novel technique for designing a radiator suitable for personal neutron dosemeter based on plastic track detector was discussed. A multi-layer structure has been proposed in the previous report, where the thicknesses of plural polyethylene (PE) layers and insensitive ones were determined by iterative calculations of double integral. In order to arrange this procedure and make it more systematic, unfolding calculation has been employed to estimate an ideal radiator containing an arbitrary hydrogen concentration. In the second step, realistic materials replaced it with consideration of minimisation of the layer number and commercial availability. A radiator consisting of three layers of PE, Upilex and Kapton sheets was finally designed, for which a deviation in the energy dependence between 0.1 and 20 MeV could be controlled within 18 %. An applicability of fluorescent nuclear track detector element has also been discussed. [ABSTRACT FROM AUTHOR]