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Background: Understanding the evolution of migration requires knowledge of the patterns, sources, and consequences of variation in migratory behaviour, a need exacerbated by the fact that many migratory species show rapid population declines and require knowledge-based conservation measures. We therefore need detailed knowledge on the spatial and temporal distribution of individuals across their annual cycle, and quantify how the spatial and temporal components of migratory behaviour vary within and among individuals. Methods: We tracked 138 migratory journeys undertaken by 64 adult common terns (Sterna hirundo) from a breeding colony in northwest Germany to identify the annual spatiotemporal distribution of these birds and to evaluate the individual repeatability of eleven traits describing their migratory behaviour. Results: Birds left the breeding colony early September, then moved south along the East Atlantic Flyway. Wintering areas were reached mid-September and located at the west and south coasts of West Africa as well as the coasts of Namibia and South Africa. Birds left their wintering areas late March and reached the breeding colony mid-April. The timing, total duration and total distance of migration, as well as the location of individual wintering areas, were moderately to highly repeatable within individuals (repeatability indexes: 0.36–0.75, 0.65–0.66, 0.93–0.94, and 0.98–1.00, respectively), and repeatability estimates were not strongly affected by population-level inter-annual variation in migratory behaviour. Conclusions: We found large between-individual variation in common tern annual spatiotemporal distribution and strong individual repeatability of several aspects of their migratory behaviour. [ABSTRACT FROM AUTHOR]

Aflatoxin, a carcinogenic toxin, is produced mainly by Aspergillus flavus and Aspergillus parasiticus. Contamination of maize (Zea mays L.) grain by these fungi occurs before harvest, and the easiest strategy to prevent this is to develop/use maize varieties resistant to Aspergillus spp. and aflatoxin accumulation. The objective of this investigation was to identify potential sources of resistance among 23 maize inbred lines (13 obtained from the MAIZE Competitive Grants Initiative, International Maize and Wheat Improvement Centre and 10 from Agricultural Research Council, South Africa). The inbred lines were planted in a randomized complete-block design at two locations each in Kenya and South Africa. Maize ears were inoculated at silking with three toxigenic strains of A. flavus. The inoculated ears in each plot were harvested at 12–18% moisture, dried, and visually assessed for Aspergillus ear rot (AER). Aflatoxin concentration in the kernels was determined using liquid chromatography–tandem mass spectrometry. Significant variation for both AER and aflatoxin concentration existed among the inbred lines at both locations in Kenya and one location in South Africa. Combined analysis revealed a significant (p < 0.001) lines × locations interaction for both AER and aflatoxin concentration. Higher incidences of AER (0–86.0%) and aflatoxin concentration (0.21–6.51 µg/kg) were recorded at Kiboko in Kenya than at the other three locations. A stronger genetic correlation (rG = 0.936, p < 0.0001) between the AER and aflatoxin concentration was recorded in Potchefstroom than at the other three locations. Repeatability of aflatoxin concentration was high at Kiboko (0.87) and Potchefstroom in South Africa (0.74). Three inbred lines, CML247, CML444, and CML495, emerged as potentially useful sources of resistance to AER and aflatoxin accumulation as they showed low levels of aflatoxin contamination in both localities in Kenya and in South Africa. [ABSTRACT FROM AUTHOR]

The pine pitch canker fungus,Fusarium circinatum, has caused large-scale mortality ofPinus patulaSchiede & Deppe ex Schltdl. & Cham. crops in South African nurseries. This disease is now managed with strict hygiene practices and mortality in commercial nurseries has been drastically reduced. During the last 10 years, however, the disease started to manifest in the field, impacting on post-planting survival. Tree breeders have identified selection and breeding of tolerant material as the likely long-term solution to this disease. This study demonstrates that, under greenhouse conditions with artificial inoculation of young seedlings, there is significant genetic variation in tolerance toF. circinatumamong open-pollinatedP. patulafamilies. Tolerant families can be identified and can be utilised in breeding programmes and for seed production. The study provided strong evidence that these artificial inoculation experiments are highly repeatable within specific laboratories, with lower but still meaningful repeatability between different laboratories. [ABSTRACT FROM AUTHOR]

Data validity is a very important aspect of cancer registries in ensuring data quality for research and interventions. This study focused on evaluating the repeatability of manual coding of cancer reports in the South African National Cancer Registry (NCR). This cross-sectional study used the Delphi technique to classify 48 generic tumour sites into sites that would be most likely ("difficult") and least likely ("not difficult") to give rise to discordant results among coders. Reports received from the Charlotte Maxeke Academic Hospital were manually recoded by five coders (2 301 reports, e.g. approximately 400 reports each) for intracoder agreement; and by four coders (400 reports) for inter-coder agreement. Unweighted kappa statistics were calculated and interpreted using Byrts' criteria. After four rounds of the Delphi technique, consensus was reached on the classification of 91.7% (44/48) of the sites. The remaining four sites were classified according to modal expert opinion. The overall kappa was higher for intra-coder agreement (0.92) than for inter-coder agreement (0.89). "Not difficult" tumour sites reflected better agreement than "difficult" tumour sites. Ten sites (skin other, basal cell carcinoma of the skin, connective tissue, other specified, lung, colorectal, prostate, oesophagus, naso-oropharynx and primary site unknown) were among the top 80% misclassified sites. The repeatability of manual coding at the NCR was rated as "good" according to Byrts' criteria. Misclassified sites should be prioritised for coder training and the strengthening of the quality assurance system. [ABSTRACT FROM AUTHOR]