Microbial Effects in the Context of Past German Safety Cases (KIT Scientific Reports ; 7744)

This review describes the organic inventory in the wastes in German facilities, the microbial processes, such as aerobic and anaerobic processes, sulfate reduction, pH and ionic strength ranges and chaotropic effects on microbial activity. The microbial effects are discussed for resident and introduced microorganisms and the environmental conditions. The microbial population above the Gorleben salt dome and their effects of microorganisms on the retention of technetium and selenium are shown

Structural and spatial analysis of the microbial communities in soil contaminated with polycyclic aromatic hydrocarbons

The microbial communities of an aged, creosote-contaminated soil (CMN) and an uncontaminated soil (PMN) from nearby were compared. Polymerase chain reaction (PCR) amplicons of small subunit ribosomal RNA-encoding genes were resolved on a denaturing gradient gel (DGGE) and transformed into clone libraries. The CMN community was less diverse than the PMN, as evidenced by 1) the finite number of DGGE bands versus the smeared profile of the PMN and 2) the finite number of unique clones versus the flat rank abundance of the PMN clones. The CMN clone library contained sequences belonging only to the Proteobacteria, whereas the PMN sequences represented numerous phylotypes. A soil-embedding technique was developed for visualizing microorganisms in soil that preserved spatial arrangements as compared to conventional slurry-based methods. 16S rRNA probes were hybridized to cells in three soils contaminated with polycyclic aromatic hydrocarbons (PAH) and the uncontaminated soil after incubation with pyrene. Spatial relationships between cells and pyrene were determined using a two-population stereological analysis. Microbial localization with respect to pyrene was found to be nonrandom for the slurry-based method and random for the aggregate method. This was likely due to the close association of cells and pyrene with soil particles in the slurried samples. Other patterns also emerged: 1) the higher the background PAH contamination, the more cells clustered with respect to pyrene, and 2) the clustering tendency increased over time for the least contaminated soil and decreased for the others. These data suggest that better-adapted populations are present in more contaminated soils. The change in the bacterial community structure of the spiked PMN was monitored by PCR-DGGE. The PMN profile became less diverse over time but never approached that of the CMN, even after an additional pyrene spike. The community did not recover its original diversity, indicating either permanent succession or an ongoing selection of certain populations due to constant contaminant availability in the soil. A group of pyrene degraders, PG3, was detected whose 16S rRNA gene copy number correlated with pyrene mineralization, suggesting that the appearance of this group following an acute exposure to PAH could be an indicator of remediation potential

Search for stop and higgsino production using diphoton Higgs boson decays

Results are presented of a search for a "natural" supersymmetry scenario with gauge mediated symmetry breaking. It is assumed that only the supersymmetric partners of the top-quark (stop) and the Higgs boson (higgsino) are accessible. Events are examined in which there are two photons forming a Higgs boson candidate, and at least two b-quark jets. In 19.7 inverse femtobarns of proton-proton collision data at sqrt(s) = 8 TeV, recorded in the CMS experiment, no evidence of a signal is found and lower limits at the 95% confidence level are set, excluding the stop mass below 360 to 410 GeV, depending on the higgsino mass

Severe early onset preeclampsia: short and long term clinical, psychosocial and biochemical aspects

Preeclampsia is a pregnancy specific disorder commonly defined as de novo hypertension and proteinuria after 20 weeks gestational age. It occurs in approximately 3-5% of pregnancies and it is still a major cause of both foetal and maternal morbidity and mortality worldwide1. As extensive research has not yet elucidated the aetiology of preeclampsia, there are no rational preventive or therapeutic interventions available. The only rational treatment is delivery, which benefits the mother but is not in the interest of the foetus, if remote from term. Early onset preeclampsia (<32 weeks’ gestational age) occurs in less than 1% of pregnancies. It is, however often associated with maternal morbidity as the risk of progression to severe maternal disease is inversely related with gestational age at onset2. Resulting prematurity is therefore the main cause of neonatal mortality and morbidity in patients with severe preeclampsia3. Although the discussion is ongoing, perinatal survival is suggested to be increased in patients with preterm preeclampsia by expectant, non-interventional management. This temporising treatment option to lengthen pregnancy includes the use of antihypertensive medication to control hypertension, magnesium sulphate to prevent eclampsia and corticosteroids to enhance foetal lung maturity4. With optimal maternal haemodynamic status and reassuring foetal condition this results on average in an extension of 2 weeks. Prolongation of these pregnancies is a great challenge for clinicians to balance between potential maternal risks on one the eve hand and possible foetal benefits on the other. Clinical controversies regarding prolongation of preterm preeclamptic pregnancies still exist – also taking into account that preeclampsia is the leading cause of maternal mortality in the Netherlands5 - a debate which is even more pronounced in very preterm pregnancies with questionable foetal viability6-9. Do maternal risks of prolongation of these very early pregnancies outweigh the chances of neonatal survival? Counselling of women with very early onset preeclampsia not only comprises of knowledge of the outcome of those particular pregnancies, but also knowledge of outcomes of future pregnancies of these women is of major clinical importance. This thesis opens with a review of the literature on identifiable risk factors of preeclampsia

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Un grand statuaire : David d'Angers, sa vie, ses oeuvres / par son fils

<div><p>Rock salt represents a potential host rock formation for the final disposal of radioactive waste. The interactions between indigenous microorganisms and radionuclides, e.g. uranium, need to be investigated to better predict the influence of microorganisms on the safety assessment of the repository. Hence, the association process of uranium with two microorganisms isolated from rock salt was comparatively studied. <i>Brachybacterium</i> sp. G1, which was isolated from the German salt dome Gorleben, and <i>Halobacterium noricense</i> DSM15987^T, were selected as examples of a moderately halophilic bacterium and an extremely halophilic archaeon, respectively. The microorganisms exhibited completely different association behaviors with uranium. While a pure biosorption process took place with <i>Brachybacterium</i> sp. G1 cells, a multistage association process occurred with the archaeon. In addition to batch experiments, <i>in situ</i> attenuated total reflection Fourier-transform infrared spectroscopy was applied to characterize the U(VI) interaction process. Biosorption was identified as the dominating process for <i>Brachybacterium</i> sp. G1 with this method. Carboxylic functionalities are the dominant interacting groups for the bacterium, whereas phosphoryl groups are also involved in U(VI) association by the archaeon <i>H</i>. <i>noricense</i>.</p></div

Phylogenetic dendrogram (neighbor-joining method) of <i>Brachybacterium</i> sp. G1 and its closest phylogenetic relatives based on an alignment of 16S rRNA gene sequences (aligned with ClustalX-MEGA 6.06).

<p>GenBank accession numbers are shown in brackets.</p

Growth of <i>Brachybacterium</i> sp. G1 as a function of ionic strength and salt composition.

<p>Circles indicate NaCl containing media, squares indicate the addition of MgCl₂.</p

Sampling area from the Gorleben halite in a depth of 840 m within the Knäulsalz layer.

<p>Sampling area from the Gorleben halite in a depth of 840 m within the Knäulsalz layer.</p