Waardering van de site Bergstraat te Oud-Turnhout (Oud-Turnhout, provincie Antwerpen) in het kader van een eventuele toekomstige bescherming

Dit rapport is de neerslag van de archeologische waardering van de site Bergstraat die plaats vond in de zomer van 2008 in het natuurgebied De Liereman te Oud-Turnhout. Naast de waardering van deze oppervlakte site zelf, in functie van een eventuele toekomstige bescherming als archeologische site, behoorde ook het evalueren van de relatie met de site Arendonk Korhaan tot de doelstelling van de studieopdracht. Met het oog op de afbakening van de site werd nagegaan in hoeverre Oud-Turnhout Bergstraat en Arendonk Korhaan beschouwd en beschermd konden worden als één groot sitecomplex. De methode om deze doelstellingen te bereiken omvatte een landschappelijke kartering, een archeologische kartering met behulp van een booronderzoek en het graven van proefputten om de stratigrafische positie en bewaring van de artefacten en hun ruimtelijk verband na te gaan. Alle steekproeven op de rug langs de zuidrand van De Liereman leverden archeologische sites op in goed bewaarde bodems. Meestal is er een podzolbodem aanwezig met hierin artefactconcentraties, maar op verschillende locaties werden bovendien Federmesserartefacten uit een Usselobodem gerecupereerd. Dit is het geval in zone 2, langs de Bergstraat en in zone 4, op de Korhaan. Samen met het feit dat ze zich op dezelfde landschappelijke eenheid bevinden, is de aanwezigheid van artefactconcentraties voldoende continu om deze zones als deel van hetzelfde uitgestrekt sitecomplex te beschouwen. Hiermee loopt het gekende sitescomplex te Arendonk Korhaan tot ver over de site Oud-Turnhout Bergstraat door, waarbij de totale lengte minstens 3km bedraagt. Om naamsverwarring tussen sites en gemeenten te vermijden stellen de auteurs voor om het volledige sitecomplex eenvoudig als De Liereman te benoemen. De bewaring van finaalpaleolithicum in een begraven Usselobodem, en in het bijzonder de gestratifieerde context in zone 4, is momenteel uniek in de regio en biedt uitzonderlijke mogelijkheden voor verder onderzoek. Het hiermee geassocieerde veenpakket vult dit potentieel verder aan wat betreft paleoecologie, terwijl de site ook veel te bieden heeft voor geomorfologisch onderzoek van deze laatglaciale ruggen. Het complex bevindt zich bovendien in een ruimer prehistorisch landschap, waarbij het onderzoek in de noordelijke zone 5 een inzicht in de aanwezigheid van het middenpaleolithicum biedt. Dit uitzonderlijk grote, rijke en goed bewaarde sitecomplex verdient volgens dit rapport niet enkel een bescherming met aangepast beheer, maar ook verder onderzoek. De hier beschreven waarnemingen roepen tal van onderzoeksvragen op die het wetenschappelijke potentieel van de site bevestigen

Cortisol administration enhances the coupling of midfrontal delta and beta oscillations

Wetensch. publ. refereedFaculteit der Sociale Wetenschappe

Cortisol administration enhances the coupling of midfrontal delta and beta oscillations

Wetensch. publ. refereedFaculteit der Sociale Wetenschappe

A reservoir of 'historical' antibiotic resistance genes in remote pristine Antarctic soils

Background: Soil bacteria naturally produce antibiotics as a competitive mechanism, with a concomitant evolution, and exchange by horizontal gene transfer, of a range of antibiotic resistance mechanisms. Surveys of bacterial resistance elements in edaphic systems have originated primarily from human-impacted environments, with relatively little information from remote and pristine environments, where the resistome may comprise the ancestral gene diversity. Methods: We used shotgun metagenomics to assess antibiotic resistance gene (ARG) distribution in 17 pristine and remote Antarctic surface soils within the undisturbed Mackay Glacier region. We also interrogated the phylogenetic placement of ARGs compared to environmental ARG sequences and tested for the presence of horizontal gene transfer elements flanking ARGs. Results: In total, 177 naturally occurring ARGs were identified, most of which encoded single or multi-drug efflux pumps. Resistance mechanisms for the inactivation of aminoglycosides, chloramphenicol and beta-lactam antibiotics were also common. Gram-negative bacteria harboured most ARGs (71%), with fewer genes from Gram-positive Actinobacteria and Bacilli (Firmicutes) (9%), reflecting the taxonomic composition of the soils. Strikingly, the abundance of ARGs per sample had a strong, negative correlation with species richness (r=-0.49, P < 0.05). This result, coupled with a lack of mobile genetic elements flanking ARGs, suggests that these genes are ancient acquisitions of horizontal transfer events. Conclusions: ARGs in these remote and uncontaminated soils most likely represent functional efficient historical genes that have since been vertically inherited over generations. The historical ARGs in these pristine environments carry a strong phylogenetic signal and form a monophyletic group relative to ARGs from other similar environments

Jabba: hybrid error correction for long sequencing reads

Background: Third generation sequencing platforms produce longer reads with higher error rates than second generation technologies. While the improved read length can provide useful information for downstream analysis, underlying algorithms are challenged by the high error rate. Error correction methods in which accurate short reads are used to correct noisy long reads appear to be attractive to generate high-quality long reads. Methods that align short reads to long reads do not optimally use the information contained in the second generation data, and suffer from large runtimes. Recently, a new hybrid error correcting method has been proposed, where the second generation data is first assembled into a de Bruijn graph, on which the long reads are then aligned. Results: In this context we present Jabba, a hybrid method to correct long third generation reads by mapping them on a corrected de Bruijn graph that was constructed from second generation data. Unique to our method is the use of a pseudo alignment approach with a seed-and-extend methodology, using maximal exact matches (MEMs) as seeds. In addition to benchmark results, certain theoretical results concerning the possibilities and limitations of the use of MEMs in the context of third generation reads are presented. Conclusion: Jabba produces highly reliable corrected reads: almost all corrected reads align to the reference, and these alignments have a very high identity. Many of the aligned reads are error-free. Additionally, Jabba corrects reads using a very low amount of CPU time. From this we conclude that pseudo alignment with MEMs is a fast and reliable method to map long highly erroneous sequences on a de Bruijn graph

Comparative metagenomic analysis reveals mechanisms for stress response in hypoliths from extreme hyperarid deserts

Understanding microbial adaptation to environmental stressors is crucial for interpreting broader ecological patterns. In the most extreme hot and cold deserts, cryptic niche communities are thought to play key roles in ecosystem processes and represent excellent model systems for investigating microbial responses to environmental stressors. However, relatively little is known about the genetic diversity underlying such functional processes in climatically extreme desert systems. This study presents the first comparative metagenome analysis of cyanobacteria-dominated hypolithic communities in hot (Namib Desert, Namibia) and cold (Miers Valley, Antarctica) hyperarid deserts. The most abundant phyla in both hypolith metagenomes were Actinobacteria, Proteobacteria, Cyanobacteria and Bacteroidetes with Cyanobacteria dominating in Antarctic hypoliths. However, no significant differences between the twometagenomeswere identified. The Antarctic hypolithicmetagenome displayed a high number of sequences assigned to sigma factors, replication,recombination andrepair, translation, ribosomal structure,andbiogenesis. In contrast, theNamibDesert metagenome showed a high abundance of sequences assigned to carbohydrate transport and metabolism. Metagenome data analysis also revealed significantdivergence inthe geneticdeterminantsof aminoacidandnucleotidemetabolismbetween these two metagenomes and those of soil from other polar deserts, hot deserts, and non-desert soils. Our results suggest extensive niche differentiation in hypolithic microbial communities from these two extreme environments and a high genetic capacity for survival under environmental extremes.Fil: Le, Phuong Thi. University of Pretoria; Sudáfrica. Vlaams Instituut voor Biotechnologie; Bélgica. University of Ghent; BélgicaFil: Makhalanyane, Thulani P.. University of Pretoria; SudáfricaFil: Guerrero, Leandro Demián. University of Pretoria; Sudáfrica. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; ArgentinaFil: Vikram, Surendra. University of Pretoria; SudáfricaFil: Van De Peer, Yves. University of Pretoria; Sudáfrica. Vlaams Instituut voor Biotechnologie; Bélgica. University of Ghent; BélgicaFil: Cowan, Don A.. University of Pretoria; Sudáfric

Cortisol-induced enhancement of emotional face processing in social phobia depends on symptom severity and motivational context.

FSW - Self-regulation models for health behavior and Psychopathology - Ou

Aesthetics and literature : a problematic relation?

The paper argues that there is a proper place for literature within aesthetics but that care must be taken in identifying just what the relation is. In characterising aesthetic pleasure associated with literature it is all too easy to fall into reductive accounts, for example, of literature as merely "fine writing". Belleslettrist or formalistic accounts of literature are rejected, as are two other kinds of reduction, to pure meaning properties and to a kind of narrative realism. The idea is developed that literature-both poetry and prose fiction-invites its own distinctive kind of aesthetic appreciation which far from being at odds with critical practice, in fact chimes well with it

Semigroup evolution in Wigner Weisskopf pole approximation with Markovian spectral coupling

We establish the relation between the Wigner-Weisskopf theory for the description of an unstable system and the theory of coupling to an environment. According to the Wigner-Weisskopf general approach, even within the pole approximation (neglecting the background contribution) the evolution of a total system subspace is not an exact semigroup for the multi-channel decay, unless the projectors into eigesntates of the reduced evolution generator $W(z)$ are orthogonal. In this case these projectors must be evaluated at different pole locations $z_\alpha\neq z_\beta$. Since the orthogonality relation does not generally hold at different values of $z$, for example, when there is symmetry breaking, the semigroup evolution is a poor approximation for the multi-channel decay, even for a very weak coupling. Nevertheless, there exists a possibility not only to ensure the orthogonality of the $W(z)$ projectors regardless the number of the poles, but also to simultaneously suppress the effect of the background contribution. This possibility arises when the theory is generalized to take into account interactions with an environment. In this case $W(z)$, and hence its eigenvectors as well, are {\it independent} of $z$, which corresponds to a structure of the coupling to the continuum spectrum associated with the Markovian limit.Comment: 9 pages, 3 figure