Coupling nearshore and aeolian processes: XBeach and duna process-based models

A new dune profile model, Duna, is developed and coupled with the existing XBeach model, in which some key improvements allow a much better behaviour of the intertidal beach and the inclusion of structural erosion or accretion through a longshore transport gradient. The model is shown to represent typical behaviour of a beach-dune system in Praia de Faro, Portugal and to be able to simulate processes on a decadal timescale. The model captures a balance between longshore gradients and cross-shore processes in the surf zone, competing effects of moderate conditions and storms in the intertidal area and between build-up by storm waves and aeolian transport on the berm. Vegetation behaviour is shown to play a key role in the development of the shape of the foredunes. The relation between progradation or recession rate and foredune height as often reported in literature is reproduced and explained.FCT Investigator program [IF/01047/2014]Portuguese Science Foundation (FCT)Portuguese Foundation for Science and Technology [28949, UID/MAR/00350/2013]FEDER FundsEuropean Union (EU)info:eu-repo/semantics/publishedVersio

Simulating destructive and constructive morphodynamic processes in steep beaches

Short-term beach morphodynamics are typically modelled solely through storm-induced erosion, disregarding post-storm recovery. Yet, the full cycle of beach profile response is critical to simulating and understanding morphodynamics over longer temporal scales. The XBeach model is calibrated using topographic profiles from a reflective beach (Faro Beach, in S. Portugal) during and after the incidence of a fierce storm (Emma) that impacted the area in early 2018. Recovery in all three profiles showed rapid steepening of the beachface and significant recovery of eroded volumes (68–92%) within 45 days after the storm, while berm heights reached 4.5–5 m. Two calibration parameters were used (facua and bermslope), considering two sets of values, one for erosive (Hm0 ≥ 3 m) and one for accretive (Hm0 < 3 m) conditions. A correction of the runup height underestimation by the model in surfbeat mode was necessary to reproduce the measured berm elevation and morphology during recovery. Simulated profiles effectively capture storm erosion, but also berm growth and gradual recovery of the profiles, showing good skill in all three profiles and recovery phases. These experiments will be the basis to formulate event-scale simulations using schematized wave forcing that will allow to calibrate the model for longer-term changes.This research was funded by FCT (Fundação para a Ciência e a Tecnologia), Portugal, in the framework of the ENLACE project, grant number PTDC/CTA-GFI/28949/2017info:eu-repo/semantics/publishedVersio

Blood coagulation factor X exerts differential effects on adenovirus entry into human lymphocytes

It has been proposed that blood coagulation factors, principally factor X (FX), enhance the uptake of human adenovirus type 5 (Ad5) into cultured epithelial cells by bridging the viral hexon capsid protein and cell-surface heparan sulphate proteoglycans (HSPGs). We studied the effects of FX on Ad transduction of lymphoid cell lines (NK92MI, a natural killer cell line; Daudi, a B-cell line and Jurkat, a T-cell line) as well as primary peripheral blood lymphocytes (PBL) and HeLa epithelial cells using either replication-deficient Ad5, or a derivative in which the Ad5 fiber was replaced with that of another Ad type, Ad35, termed Ad5F35. PBL and NK92MI were resistant to Ad5 transduction. Transduction of Jurkat and Daudi cells by Ad5 was reduced by FX but without discernible effects on cell-surface Ad5 binding. FX reduced virus binding and transduction of all lymphoid cell lines by Ad5F35, as well as transduction of the T- and Natural Killer (NK)-cell populations of PBL. Flow cytometry analysis showed that all lymphoid cell lines were negative for HSPG components, in contrast to HeLa cells. FX reduced transduction of an HSPG-negative mutant Chinese hamster ovary cell line (CHOpgsA745) by Ad5 and Ad5F35, with Ad5F35 binding also being reduced by FX. These results point to fiber-dependent differences (Ad5 versus Ad35 fiber) in Ad binding to and transduction of human lymphoid and epithelial cells in the presence of FX

Gheerkin de Hondt : a singer-composer in the sixteenth-century Low Countries

Gheerkin de Hondt may be classified as a fine representative of the large network of singers and composers contributing to one of the most significant periods in the history of music in the Low Countries. In this book Véronique Roelvink describes the career of this zangmeeester and composer, who was born in Bruges, probably around 1495. Based on a large number of archival sources, a reconstruction is made of Gheerkin’s daily activities in churches in Delft, Bruges and ’s-Hertogenbosch between 1521 and 1547 and of the status he achieved. The second part of this book provides the first examination of Gheerkin’s Masses, motets, chansons and lied, which proves that he was widely acquainted with the works of his contemporaries, and that he developed his own unique style, making a clear musical setting of texts his own personal trademark.Collective identities and transnational networks in medieval and early modern Europe, 1000-180

Characterization of the nifA regulatory gene of Rhizonium leguminosarum PRE

This thesis describes the characterization of the nif A regulatory gene of the pea endosymbiont Rhizobiumleguminosarum PRE.Chapter I gives a general overview on the regulation of nitrogen fixation in diazotrophs, with special focus on the regulatory NifA protein. The regulation of genes involved in nitrogen fixation in two bacteria is discussed in detail: the free living Klebsiellapneumoniae and the endosymbiont of alfalfa R . meliloti . Major differences exist between these organisms where the onset of nitrogen fixation is concerned. K . pneumoniae has a general nitrogen regulatory circuitry which senses an internal biochemical signal i.e. the level of available ammonia as defined by the glutamine to 2-ketoglutarate ratio, a high ratio indicating a surplus, a low ratio a deficit. Sensing of a N-deficit results is translated, through a chain reaction of protein modifications, into activation of the regulatory NtrC product by phosphorylation. The resulting NtrC-P activates transcription of the regulatory nif LA operon, which encodes the inhibitor NifL and the activator NifA. The Klebsiella NifA thereupon activates transcription of the genes involved in nitrogen fixation. In a recently published paper David et al. (1988) suggest that the onset of nitrogen fixation in R . meliloti starts with the sensing of the external oxygen level. The FixL protein is hypothesized to sense a decrease in oxygen level. This protein is thus activated and in turn activates the FixJ protein, which directly or indirectly activates transcription of the nif A gene. The Rhizobium NifA protein activates transcription of the nitrogen fixation genes. In this overview we hypothesize that the oxygen sensing protein FNR instead of FixL senses the internal oxygen level. FNR then activates transcription of the fix LJ operon. The FixL protein may be a moderator of the activity of FixJ, comparable to the role of NtrB in activating NtrC. To date all rhizobial NifA proteins, in contrast to Klebsiella NifA, were shown to be oxygen sensitive. The structural analysis of the NifA protein is described and possible functions ascribed to domains identified in this protein are discussed. A model for NifA activity emerging from data presented for K . pneumoniae isdiscussed. At present a complete model cannot be presented for Rhizobiaceae . The similarities and differences between the models for K . pneumoniae and Rhizobium species are discussed.In Chapter 2 the DNA sequence and deduced amino acid sequence of R . leguminosarum PRE are presented. The amino acid sequence differs in 30 amino acids from that published for R . leguminosarum 3855 (Grönger et al., 1987). A possible explanation for this difference is discussed. The NifA Open Reading Frame (ORF) reveals two potential translation start sites, which in a heterologous E.coli background appear to be used both. The second translation start, which leads to a 488 amino acids, 53 kD protein, is preferred over the first, which leads to a 519 amino acids, 56.1 kD protein. The R . meliloti (Weber et al., 1985, Buikema et al., 1985) and B . japonicumnif A genes (Thöny et al., 1987) also have two translation start sites. It was shown for R . meliloti NifA (Beynon et al., 1988) the full length protein is the active form in an E . coli background. It is discussed that a translational preference for the second translational start site, leading to the inactive protein, as was found in pulse labeling experiments in E . coli may also exist in Rhizobium . We therefore suggest that the experiments presented by Beynon et al. (1988) are not conclusive as to the size of the functional protein in a Rhizobium background. Primer extension experiments and S 1 -nuclease protection were used to identify the putative nif A promoter. A transcription terminator was identified by S1-nuclease protection.Chapter 3 deals with a phenomenon reported by Hawkins and Johnston (1988) and Roelvink et al. (1988). A nif A::Tn 5 mutant can not be complemented by a plasmid having only the nif A coding DNA fragment. A detailed analysis of the nif A- nif B intergenic region is presented. The nif A gene has a transcriptional terminator typical of bacterial genes (Brendel et al., 1986) consisting of a four GC basepairs stem and a nine base loop followed by a thymidine rich DNA stretch. This terminator was sapped by S1-nuclease protection. The nif B gene has a RpoN dependent promoter, having all nucleotides thought to be crucial to its activity. The nif A terminator was fused to the Tet - promoter and this fusion was cloned in a low copytranscriptional lac Z vector. The results show that the nif A terminator allows 85% readthrough. RNA::DNA hybridisation studies show that the nif A gene is transcribed at a level twice of that of nif B. By using a plasmid, which has a DNA region encompassing nif A, nif B and a ferredoxin like gene downstream of nifB (Grönger et al., 1988, Klipp et al., 1988) it was shown that nif A::Tn 5 mutants can be fully complemented. Taken together these findings suggest that the nif A and the nifB gene are in one operon. The failure of plasmids having the nifA encoding DNA fragment alone to complement a nif A::Tn 5 mutant results from a polar effect of the Tn 5 transposon on nif B transcription.Chapter 4 deals with the nif H promoter region of R . leguminosarum PRE as one of the target sites of the NifA protein. We determined the nucleotide sequence of this region and identified a pseudo upstream activator sequence (UAS), a pseudo promoter, a consensus UAS and a consensus promoter. The promoter, mapped by primer extension experiments, differs from the consensus in one of the nucleotides thought to be invariant (see Gussin et al., 1986). The function of the nif H promoter elements was tested in a heterolo gous E . coli and a homologous Rhizobium background. Fusions of the nif H promoter region to lac Z, and fusions of deleted nif H promoter regions to lac Z, were used in activation studies byE .pneumoniae NifA in E . coli . Both high and low copy (deletion) nif H:: lac Z fusions were conjugated to Rhizobium . The activation study in an E . coli background showed that the pseudo UAS and the pseudo promoter are not involved in the function of the promoter. A different result was obtained with low copy nif H:: lac Z constructs in a Rhizobium background. The construct having both pseudo and consensus UAS, when compared with a construct having the consensus UAS only, seems to delay the onset of nitrogen fixation by three days. We suggest that this indicates that the presence of one or more UAS's modulates the expression of nif and fix genes, as was suggested for UAS's of B . Japonicumnif and fix genes (Gubler and Hennecke, 1988). A nif promoter region holding a UAS, when cloned in a multi copy vector, can inhibit nitrogen fixation by capturing the NifA activator needed for expression of nif and fix genes. A multicopy Inhibition study with (deleted) nif H:: lac Zfusions led to a surprising finding: deletion of part of the consensus UAS on the multicopy plasmid did not result in inhibition of nitrogen fixation. The relevance of this finding is discussed. We conclude that R . leguminosarumnif H can function without an UAS as was found forR .meliloti nifH inplanta (Better et al., 1985). We suggest that NifA way form a complex withRpoN-RNAPthat can bind directly at the promoter to activate transcription.</TT

Assessing climate change impacts on the stability of small tidal inlets:Part 1 - Data poor environments

Bar-built or barrier estuaries (here referred to as Small tidal inlets, or STIs), which are commonly found along wave-dominated, microtidal mainland coasts, are highly likely to be affected by climate change (CC). Due to their pre-dominance in tropical and sub-tropical regions of the world, many STIs are located in developing countries, where STI related activities contribute significantly to the national GDPs while community resilience to coastal changes is low, with the corollary that CC impacts on STIs may lead to very serious socio-economic consequences. While assessing CC impacts on tidal inlets is in general difficult due to inherent limitations of contemporary numerical models where long term morphodynamic simulations are concerned, these difficulties are further exacerbated due to the lack of sufficient model input/verification data in often data poor developing country STI environs. As a solution to this problem, Duong et al. (2016) proposed two different process based snap-shot modelling approaches for data poor and data rich environments. This article demonstrates the application of Duong et al.'s (2016) snap-shot modelling approach for data poor environments to 3 case study sites representing the 3 main STI types; Permanently open, locationally stable inlets (Type 1), Permanently open, alongshore migrating inlets (Type 2) and Seasonally/Intermittently open, locationally stable inlets (Type 3). Results show that Type 1 and Type 3 inlets will not change Type even under the most extreme CC driven variations in system forcing considered here. Type 2 inlets may change into Type 1 when CC results in a reduction in annual longshore sediment transport. Apart from Type changes, CC will affect the level of inlet stability and some key behavioural characteristics (e.g. inlet migration distances, inlet closure times). In general, CC driven variations in annual longshore sediment transport rates appear to be more relevant for future changes in inlet stability and behaviour, rather than sea level rise as commonly believed. Based on model results, an inlet classification scheme which, for the first time, links inlet Type with the Bruun inlet stability criteria is presented

Vitamin-K-Antagonisten und Blutungen ins zentrale Nervensystem

Neurochirurgisch relevante Blutungen unter oraler Antikoagulation (OAC) sind die meist gefürchtete Komplikation. Trotzdem wurden bisher keine ausreichenden Studien hierzu durchgeführt. Die vorliegende Arbeit liefert Daten zu offenen Fragen bezüglich der Inzidenz im Zeitraum 2002-2003 im Einzugsgebiet Münster, Risikofaktoren, Indikationen, Klinik und Bildgebung, Gerinnungsstatus, Therapie und Erholungszustand ein Jahr nach Auftreten der Blutung. Es traten pro Jahr 22 ICBs unter OAC auf, ein 7-18facher höherer Wert im Vergleich eine ICB ohne OAC zu erleiden. Durch die geringe Meldungsrate können die unklaren Daten der unerwünschten Wirkungen nicht in eine wirklichkeitsnahe Beziehung zu den erwünschten Wirkungen gesetzt werden. Das Ziel wäre eine Vervollkommnung der Erfassung von Blutungskomplikationen, sowie ein interdisziplinär akzeptierter Standard zur Langzeitanwendung von Vitamin-K-Antagonisten, unter Würdigung der von Neurochirurgen publizierten, erheblichen Nebenwirkungen

Morphological modelling of the Western Scheldt: validation of DELFT3D

Morphological changes of the Scheldt estuary are extensively monitored by the Dutch and Belgian authorities. To predict effects of long-term natural changes (sea level rise) and the consequences of various human interventions, such as dredging/dumping/sand mining and deepening of the navigation channel, there is an urgent need for adequate and reliable tools in these matters. The present report describes the results of the calibration and verification of the DEFLT3D morphological model for the Western Scheldt on the short term (years) as well as on the mid term (decades)