Middle and late Holocene vegetation and landscape evolution of the Scheldt estuary : a palynological study of a peat deposit from Doel (Belgium)

Local and regional environmental conditions for the south-eastern Scheldt estuary during the middle and late Holocene period have been reconstructed based on pollen analysis, loss-on-ignition and radiocarbon dating of a sediment core from Doe (N-Belgium) and the comparison with existing data from other sites from the same region. Postglacial relative sea level rise resulted in the formation of alder carr vegetation in the lower parts of the landscape from c. 7640 cal BP onwards. The vegetation succession was weakly influenced by the deposition of tidal clay deposits between c. 6550 and 5650 a cal BP and eventually culminated in the development of an oligotrophic bog. Peat accumulation seems to have ceased between c. 2030 and 1220 a cal BP, well before it was covered by marine sediments in the late Middle Ages

Effect of multiple allelic drop-outs in forensic RMNE calculations

Technological advances such as massively parallel sequencing enable increasing amounts of genetic information to be obtained from increasingly challenging samples. Certainly on low template, degraded and multi-contributor samples, drop-outs will increase in number for many profiles simply by analyzing more loci, making it difficult to probabilistically assess how many drop-outs have occurred and at which loci they might have occurred. Previously we developed a Random Man Not Excluded (RMNE) method that can take into account allelic drop-out while avoiding detailed estimations of the probability that drop-outs have occurred, nor making assumptions about at which loci these drop-outs might have occurred. The number of alleles that have dropped out, does not need to be exactly known. Here we report a generic Python algorithm to calculate the RMNE probabilities for any given number of loci. The number of allowed drop-outs can be set between 0 and twice the number of analyzed loci. The source code has been made available on https://github.com/fvnieuwe/rmne. An online web-based RMNE calculation tool has been made available on http://forensic.ugent.be/rmne. The tool can calculate these RMNE probabilities from a custom list of probabilities of the observed and non-observed alleles from any given number of loci. Using this tool, we explored the effect of allowing allelic drop-outs on the evidential value of random forensic profiles with a varying number of loci. Our results give insight into how the number of allowed drop-outs affects the evidential value of a profile and how drop-out can be managed in the RMNE approach

Forensic SNP genotyping using nanopore MinION sequencing

One of the latest developments in next generation sequencing is the Oxford Nanopore Technologies' (ONT) MinION nanopore sequencer. We studied the applicability of this system to perform forensic genotyping of the forensic female DNA standard 9947 A using the 52 SNP-plex assay developed by the SNPforID consortium. All but one of the loci were correctly genotyped. Several SNP loci were identified as problematic for correct and robust genotyping using nanopore sequencing. All these loci contained homopolymers in the sequence flanking the forensic SNP and most of them were already reported as problematic in studies using other sequencing technologies. When these problematic loci are avoided, correct forensic genotyping using nanopore sequencing is technically feasible

Inventarisatie van het paleo-ecologisch bodemarchief voor archeologisch onderzoek en bescherming

In recent years palaeoecological research has gained a lot of interest within the field of archaeology. It is used for the reconstruction of the past environment as well as for studying the interaction between man and his environment during (pre)historic times. Also in matters of nature conservation and development palaeoecological research enjoys more and more attention, for establishing reference images and insight in landscape and vegetation history. Moreover, nowadays people become aware of the fact that the palaeoecological natural archive is vulnerable and threatened. For these reasons the need was felt for a systematic overview of all the palynological research in Flanders, published and unpublished, from both archaeological sites and natural sequences. Up to now this database comprises 35 sites and 0 radiocarbon dates. Goals were to make the palynological data available for wider use and to preserve palynologicaly experience and knowledge. In addition some ideas for the management of places with a high palaeoecological potential have been outlined. The cases of the Mark valley and the Kale valley have further been explored for actual conservation and protection of the natural site