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Abstract: During the period 2004–2008 the distribution, settlement, and growth of first-year shipworms (Teredo navalis L., 1758) was studied by exposing fir and oak panels in the Port of Rotterdam area, which is situated in the Rhine-Meuse estuary in the Netherlands and covers the complete salinity gradient. Shipworms were found yearly in the western large polyhaline harbours. On only a few occasions were they were found in harbours that showed large seasonal and daily fluctuations in salinity. In 2006 the shipworm was found in fir panels 20km upstream from the polyhaline harbours, demonstrating their ability to travel with the tidal currents over considerable distances and to settle once the abiotic conditions become favourable. Although the water temperatures allowed them to breed from April until November, infestations were not found before September, and from the size of the animals in the panels it was concluded that in the Port of Rotterdam area they spawned from August until the end of November. The settlement height was negatively correlated with the distance of the panels to the sea floor. In the first season after settlement they showed a substantial growth rate of 0.18cmday−1. The longest shipworm found measured 36.8cm after 4–5 months of growth after settlement. Infestations and growth were lower in oak than in fir wood. In 2006 the maximum consumption of wood by individuals settled in the same year in panels at the bottom accounted for 12.4%. Shell size and body length of the animal after the first season of growth showed a significant positive logarithmic relation. In both 2006 and 2007 a similar relation between the average boring tube diameter and the length of the animals was found. Lower river discharges leading to salinisation of the eastern part of the Port of Rotterdam area create conditions favourable for the shipworm, with serious consequences for the piles upon which the quays are built. [Copyright &y& Elsevier]

In this study, two data collection instruments were used to examine how Dutch secondary school teachers learn in the workplace. Firstly, they completed a questionnaire on their preferences for learning activities on two occasions. Secondly, during the intermediate period, they reported learning experiences in digital logs. Results of both instruments indicate that teachers often learn by critical individual reflection and by involving colleagues in particular challenging or problematic situations. An additional finding concerns the reporting of sequences of learning activities in the digital logs which is clearly different from the focus on single learning activities as found in most literature and as used in the questionnaire. Furthermore, the digital logs provided a fine-tuning of the concepts of 'involvement of colleagues' and 'experimentation' in relation to teacher learning. The study concludes with a critical reflection on both data collection instruments. Finally, implications for future research on how teachers learn are discussed. [ABSTRACT FROM AUTHOR]

We investigate the determinants of geographical distances to parents. We focus on the role of family members who live outside the household (the parents themselves, and siblings), and on the distinction between the effects of life events and effects related to the timing with which these events have been experienced in the life course. We use data from the Netherlands Kinship Panel Study and linear regression models on the logarithm of distance. We find that life-course characteristics are much more important to the distance to parents than parental characteristics. Sibling characteristics, most notably the presence of a sister, also have an impact on this distance. [ABSTRACT FROM AUTHOR]

Background: Atrial Fibrillation (AF), the most common cardiac arrhythmia, is a significant public health problem in the United States, affecting approximately 2.2 million Americans. Recently, several chromosomal loci and genes have been found to be associated with familial AF. However, in most other AF cases, the genetic basis is still poorly understood.Objective: The purpose of this study was to investigate the molecular basis of familial AF in a Dutch kindred group.Methods: We analyzed a four-generation Dutch family in which AF segregated as an autosomal dominant trait. After the exclusion of linkage to 10q22-24, 6q14-16, 5p13, KCNQ1, KCNE2, KCNJ2 and some ion-channel-associated candidate genes, a genome-wide linkage scan using 398 microsatellite markers was performed.Results: Two-point logarithms of odds (LOD) scores >1 at recombination fraction [theta] = 0.00 and a haplotype segregating with the disorder were demonstrated only across regions of chromosome 10. Subsequent fine mapping gave a maximum two-point LOD score of 4.1982 at D10S568 at [theta] = 0.00. Distinct recombination in several individuals narrowed the shared region among all affected individuals to 16.4 cM on the Genethon map (flanking markers: D10S578 and D10S1652), which corresponds to chromosome 10p11-q21. Thirteen candidate genes residing in this region, which could be associated with AF, were screened. No mutation has been found in their coding regions including the intron splice regions.Conclusion: We identify a novel locus for AF on chromosome 10p11-q21, which provides further evidence of genetic heterogeneity in this arrhythmia. [ABSTRACT FROM AUTHOR]