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Therapeutic peptides are highly potent and specific in their functions, but difficulties in their administration require parallel development of viable delivery systems to improve their bioavailability. In this study the potential of a novel lipid-based colloidal delivery system for improving the absorption of nasally and intestinally administered salmon(More)
Measurements of network parameters like bandwidths and latencies in wireless networks entail some new challenges. Especially cellular networks are highly dynamic furthermore, the potential mobility of the client can lead to frequent and spontaneous changes in the communication properties. Cellular networks are a shared medium, therefore, bandwidth is(More)
The NMISA Radioactivity Standards Laboratory participated in the CCRI(II)-S9 inter-comparison of the measurement of the activity concentration of (137)Cs and (40)K in rice material, piloted by the KRISS. The paper describes the equipment used, the measurement set-up and data analysis. The efficiency of the detector for (137)Cs and (40)K was determined by(More)
In the vision of an ambient intelligent world, innumerable small interconnected devices will surround us and support us in our daily tasks and while at leisure. To do so, these devices need to know and exchange our personal preferences. Moreover, without any built-in countermeasures these devices are more than able to collect much more private information.(More)
The radionuclides 99mTc and 57Co were standardized via absolute liquid scintillation counting techniques. We provide the first technical report on the absolute standardization of 99mTc using 4π(LS)e-γ coincidence counting. The low detection efficiency of low-energy conversion electrons translates into a large efficiency extrapolation range. A simulation(More)
This paper reports on absolute activity measurements of iron-59 made at the National Metrology Institute of South Africa (NMISA) via 4π(LS)β-γ coincidence counting. The exercise formed part of an Asia Pacific Metrology Program (APMP) regional key comparison. Source data were analysed by the extrapolation technique for a number of gamma-ray window settings.(More)
The hypothesis that proximity to the Sun causes variation of decay constants at permille level has been tested and disproved. Repeated activity measurements of mono-radionuclide sources were performed over periods from 200 days up to four decades at 14 laboratories across the globe. Residuals from the exponential nuclear decay curves were inspected for(More)
Twenty years ago South Africa's Radioactivity Standards Laboratory (now operated by the NMISA) was the first to measure the activity of (55)Fe by combining the triple-to-double coincidence ratio (TDCR) liquid scintillation method with theoretical efficiency formulae. The extracted activity was however found to be consistently low by about 6%. Due to(More)
This paper aims to inform the public and scientists not in the field of radioactivity on the way secondary activity measurements are undertaken at NMISA to ensure the quality of life of South Africans. Various secondary standard nuclear instruments are used for routine activity measurements for dissemination to the user community such as the nuclear(More)
The NMISA participated in the international key comparison of the pure beta-emitter Technetium-99, CCRI(II)-K2.Tc-99. The comparison solution was standardized using three methods, namely the TDCR efficiency calculation method, the CIEMAT/NIST efficiency tracing method and the 4π(LS)β-γ coincidence tracing method with Co-60 as tracer. Excellent agreement(More)