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Abstract Background This study describes the laboratory evaluation of a novel diagnostic platform for malaria. The Magneto Optical Test (MOT) is based on the bio-physical detection of haemozoin in clinical samples. Having an assay time of around one minute, it offers the potential of high throughput screening. Methods Blood samples of confirmed malaria patients from different regions of Africa, patients with other diseases and healthy non-endemic controls were used in the present study. The samples were analysed with two reference tests, i.e. an histidine rich protein-2 based rapid diagnostic test (RDT) and a conventional Pan-Plasmodium PCR, and the MOT as index test. Data were entered in 2 × 2 tables and analysed for sensitivity and specificity. The agreement between microscopy, RDT and PCR and the MOT assay was determined by calculating Kappa values with a 95% confidence interval. Results The observed sensitivity/specificity of the MOT test in comparison with clinical description, RDT or PCR ranged from 77.2 - 78.8% (sensitivity) and from 72.5 - 74.6% (specificity). In general, the agreement between MOT and the other assays is around 0.5 indicating a moderate agreement between the reference and the index test. However, when RDT and PCR are compared to each other, an almost perfect agreement can be observed (k = 0.97) with a sensitivity and specificity of >95%. Conclusions Although MOT sensitivity and specificity are currently not yet at a competing level compared to other diagnostic test, such as PCR and RDTs, it has a potential to rapidly screen patients for malaria in endemic as well as non-endemic countries.

In magnetic media thermal transport properties are sensitive to the large internal field associated with the magnetization. Using photo-acoustic detection, we show how measurement of the amplitude of thermal waves traversing a magnetic medium provides a technique with the potential to separate the magnetic characteristics of different layers in a multi-layer structure. The technique is demonstrated by recovering the hysteresis loops of magnetic films in tri-layer structures with thick (100 nm) nonmagnetic capping layers. Index Terms--Magnetic multi-layers, photo-acoustic detection, thermal-wave interactions.

A recording medium consisting of a dispersion of cobalt nanocrystallites is produced by the controlled rapid thermal decomposition of cobalt nitride films. Blocking temperature measurements in conjunction with transmission electron microscopy determine particle size and distribution. Isothermal and DC remanence curves are used to determine the nature and degree of particle-particle interactions. Index Terms--Magnetic recording, nanocrystallite medium, particle-particle interactions, superparamagnetic limit.

Features information on a study which used the unique interaction between thermal waves and the thermal transport properties of sub-surface layers of magnetic materials to obtain hysteresis loops and other magnetic characteristics. Dependence of high-density magnetic and magneto-optic recording technologies on the use of multi-layer magnetic film structures; Methodology of the study; Results and discussion.