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Purified immunoglobulin G (IgG) raised against Salmonella typhimurium flagellin was coupled to a range of magnetic particles. Binding of cells to the immunomagnetic particles was quantified using a bioluminescence technique. Based on the results obtained, Dynabeads were selected for further study. Various factors including the bacterial growth medium and the time and temperature of incubation affected cell binding. A 10 min incubation at ambient temperature was selected to maximise immunological binding and to minimise non‐specific interactions. Using these optimised separation parameters, S. typhimurium was enriched from a range of mixed cultures by between 3‐ and 2,700‐fold. Several commercially available genus‐specific Salmonella antisera were coupled to Dynabeads and screened for efficacy of cell binding. The optimum immunomagnetic particle system was used to separate viable Salmonella enteritidis from artificially contaminated egg yolk and detected down to a level of about 105 cfu.g‐1 in 20 min using...

The cytogenetics of several South African species of Xiphinema were studied and compared with the existing data for this genus from Europe. The process of oogenesis appears to be very similar in all species studied, with little interspecific and intraspecific differences. The ovaries of the South African specimens are larger, with more oogonia and oocytes. The chromosomes are also relatively larger, but could not be counted in oocytes during diakinesis, which usually represents the best stage. Chromosome numbers were therefore determined in the oogonia, which yielded quite accurate and consistent results. The diploid number of 10 seems to be constant in all species studied, but differs from one species of the X. americanum group, for which a number of five has been reported. Polyploids were not encountered in any of the South African specimens.

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(1878). Photography at the least-refrangible end of the solar spectrum. The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science: Vol. 6, No. 35, pp. 154-157.