| 1. |
- Aad, G., et al.
(author)
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- 2011
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swepub:Mat__t (peer-reviewed)
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| 2. |
- Schael, S., et al.
(author)
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Electroweak measurements in electron positron collisions at W-boson-pair energies at LEP
- 2013
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In: Physics Reports. - : Elsevier BV. - 0370-1573 .- 1873-6270. ; 532:4, s. 119-244
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Research review (peer-reviewed)abstract
- Electroweak measurements performed with data taken at the electron positron collider LEP at CERN from 1995 to 2000 are reported. The combined data set considered in this report corresponds to a total luminosity of about 3 fb(-1) collected by the four LEP experiments ALEPH, DELPHI, 13 and OPAL, at centre-of-mass energies ranging from 130 GeV to 209 GeV. Combining the published results of the four LEP experiments, the measurements include total and differential cross-sections in photon-pair, fermion-pair and four-fermion production, the latter resulting from both double-resonant WW and ZZ production as well as singly resonant production. Total and differential cross-sections are measured precisely, providing a stringent test of the Standard Model at centre-of-mass energies never explored before in electron positron collisions. Final-state interaction effects in four-fermion production, such as those arising from colour reconnection and Bose Einstein correlations between the two W decay systems arising in WW production, are searched for and upper limits on the strength of possible effects are obtained. The data are used to determine fundamental properties of the W boson and the electroweak theory. Among others, the mass and width of the W boson, m(w) and Gamma(w), the branching fraction of W decays to hadrons, B(W -> had), and the trilinear gauge-boson self-couplings g(1)(Z), K-gamma and lambda(gamma), are determined to be: m(w) = 80.376 +/- 0.033 GeV Gamma(w) = 2.195 +/- 0.083 GeV B(W -> had) = 67.41 +/- 0.27% g(1)(Z) = 0.984(-0.020)(+0.018) K-gamma - 0.982 +/- 0.042 lambda(gamma) = 0.022 +/- 0.019. (C) 2013 Elsevier B.V. All rights reserved.
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| 3. |
- Schael, S, et al.
(author)
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Precision electroweak measurements on the Z resonance
- 2006
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In: Physics Reports. - : Elsevier BV. - 0370-1573 .- 1873-6270. ; 427:5-6, s. 257-454
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Research review (peer-reviewed)abstract
- We report on the final electroweak measurements performed with data taken at the Z resonance by the experiments operating at the electron-positron colliders SLC and LEP. The data consist of 17 million Z decays accumulated by the ALEPH, DELPHI, L3 and OPAL experiments at LEP, and 600 thousand Z decays by the SLID experiment using a polarised beam at SLC. The measurements include cross-sections, forward-backward asymmetries and polarised asymmetries. The mass and width of the Z boson, m(Z) and Gamma(Z), and its couplings to fermions, for example the p parameter and the effective electroweak mixing angle for leptons, are precisely measured: m(Z) = 91.1875 +/- 0.0021 GeV, Gamma(Z) = 2.4952 +/- 0.0023 GeV, rho(l) = 1.0050 +/- 0.0010, sin(2)theta(eff)(lept) = 0.23153 +/- 0.00016. The number of light neutrino species is determined to be 2.9840 +/- 0.0082, in agreement with the three observed generations of fundamental fermions. The results are compared to the predictions of the Standard Model (SM). At the Z-pole, electroweak radiative corrections beyond the running of the QED and QCD coupling constants are observed with a significance of five standard deviations, and in agreement with the Standard Model. Of the many Z-pole measurements, the forward-backward asymmetry in b-quark production shows the largest difference with respect to its SM expectation, at the level of 2.8 standard deviations. Through radiative corrections evaluated in the framework of the Standard Model, the Z-pole data are also used to predict the mass of the top quark, m(t) = 173(+10)(+13) GeV, and the mass of the W boson, m(W) = 80.363 +/- 0.032 GeV. These indirect constraints are compared to the direct measurements, providing a stringent test of the SM. Using in addition the direct measurements of m(t) and m(W), the mass of the as yet unobserved SM Higgs boson is predicted with a relative uncertainty of about 50% and found to be less than 285 GeV at 95% confidence level. (c) 2006 Elsevier B.V. All rights reserved.
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| 4. |
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| 5. |
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| 6. |
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| 7. |
- Shupe, M. D., et al.
(author)
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Overview of the MOSAiC expedition : Atmosphere
- 2022
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In: Elementa. - : University of California Press. - 2325-1026. ; 10:1
-
Journal article (peer-reviewed)abstract
- With the Arctic rapidly changing, the needs to observe, understand, and model the changes are essential. To support these needs, an annual cycle of observations of atmospheric properties, processes, and interactions were made while drifting with the sea ice across the central Arctic during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition from October 2019 to September 2020. An international team designed and implemented the comprehensive program to document and characterize all aspects of the Arctic atmospheric system in unprecedented detail, using a variety of approaches, and across multiple scales. These measurements were coordinated with other observational teams to explore crosscutting and coupled interactions with the Arctic Ocean, sea ice, and ecosystem through a variety of physical and biogeochemical processes. This overview outlines the breadth and complexity of the atmospheric research program, which was organized into 4 subgroups: atmospheric state, clouds and precipitation, gases and aerosols, and energy budgets. Atmospheric variability over the annual cycle revealed important influences from a persistent large-scale winter circulation pattern, leading to some storms with pressure and winds that were outside the interquartile range of past conditions suggested by long-term reanalysis. Similarly, the MOSAiC location was warmer and wetter in summer than the reanalysis climatology, in part due to its close proximity to the sea ice edge. The comprehensiveness of the observational program for characterizing and analyzing atmospheric phenomena is demonstrated via a winter case study examining air mass transitions and a summer case study examining vertical atmospheric evolution. Overall, the MOSAiC atmospheric program successfully met its objectives and was the most comprehensive atmospheric measurement program to date conducted over the Arctic sea ice. The obtained data will support a broad range of coupled-system scientific research and provide an important foundation for advancing multiscale modeling capabilities in the Arctic.
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| 8. |
- Dunham, I, et al.
(author)
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The DNA sequence of human chromosome 22
- 1999
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In: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 402:6761, s. 489-495
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Journal article (peer-reviewed)
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| 9. |
- Journeau, C., et al.
(author)
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European Research on the Corium issues within the SARNET network of excellence
- 2008
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In: International Conference on Advances in Nuclear Power Plants, ICAPP 2008. - 9781605607870 ; , s. 1172-1181
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Conference paper (peer-reviewed)abstract
- Within SARNET, the corium topic covers all the behaviors of corium from early phase of core degradation to in or ex-vessel corium recovery with the exception of corium interaction with water, direct containment heating and fission product release. The corium topic regroups in three work packages the critical mass of competence required to improve significantly the corium behavior knowledge. The spirit of the SARNET networking is to share the knowledge, the facilities and the simulation tools for severe accidents, so to reach a better efficiency and to rationalize the R&D effort at European level. Extensive benchmarking has been launched in most of the areas of research. These benchmarks were mainly dedicated to the recalculation of experiments, while, in the next periods, a larger focus will be given to integral experiments or reactor applications. Eventually, all the knowledge will be accumulated in the ASTEC severe accident simulation code through physical model improvements and extension of validation database. This paper summarizes the progress that has been achieved in the frame of the networking activities. A special focus is placed on the melt pool and debris coolability and corium-concrete interaction, in which, the effects due to multidimensional geometries and heterogeneities has been shown, during SARNET, to play a crucial role and for which further research is still needed.
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| 10. |
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| 11. |
- Flannick, Jason, et al.
(author)
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Data Descriptor : Sequence data and association statistics from 12,940 type 2 diabetes cases and controls
- 2017
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In: Scientific Data. - : Springer Science and Business Media LLC. - 2052-4463. ; 4
-
Journal article (peer-reviewed)abstract
- To investigate the genetic basis of type 2 diabetes (T2D) to high resolution, the GoT2D and T2D-GENES consortia catalogued variation from whole-genome sequencing of 2,657 European individuals and exome sequencing of 12,940 individuals of multiple ancestries. Over 27M SNPs, indels, and structural variants were identified, including 99% of low-frequency (minor allele frequency [MAF] 0.1-5%) non-coding variants in the whole-genome sequenced individuals and 99.7% of low-frequency coding variants in the whole-exome sequenced individuals. Each variant was tested for association with T2D in the sequenced individuals, and, to increase power, most were tested in larger numbers of individuals (> 80% of low-frequency coding variants in similar to ~82 K Europeans via the exome chip, and similar to ~90% of low-frequency non-coding variants in similar to ~44 K Europeans via genotype imputation). The variants, genotypes, and association statistics from these analyses provide the largest reference to date of human genetic information relevant to T2D, for use in activities such as T2D-focused genotype imputation, functional characterization of variants or genes, and other novel analyses to detect associations between sequence variation and T2D.
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| 12. |
- Fuchsberger, Christian, et al.
(author)
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The genetic architecture of type 2 diabetes
- 2016
-
In: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 536:7614, s. 41-47
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Journal article (peer-reviewed)abstract
- The genetic architecture of common traits, including the number, frequency, and effect sizes of inherited variants that contribute to individual risk, has been long debated. Genome-wide association studies have identified scores of common variants associated with type 2 diabetes, but in aggregate, these explain only a fraction of the heritability of this disease. Here, to test the hypothesis that lower-frequency variants explain much of the remainder, the GoT2D and T2D-GENES consortia performed whole-genome sequencing in 2,657 European individuals with and without diabetes, and exome sequencing in 12,940 individuals from five ancestry groups. To increase statistical power, we expanded the sample size via genotyping and imputation in a further 111,548 subjects. Variants associated with type 2 diabetes after sequencing were overwhelmingly common and most fell within regions previously identified by genome-wide association studies. Comprehensive enumeration of sequence variation is necessary to identify functional alleles that provide important clues to disease pathophysiology, but large-scale sequencing does not support the idea that lower-frequency variants have a major role in predisposition to type 2 diabetes.
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| 13. |
- Manning, Alisa, et al.
(author)
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A Low-Frequency Inactivating AKT2 Variant Enriched in the Finnish Population Is Associated With Fasting Insulin Levels and Type 2 Diabetes Risk
- 2017
-
In: Diabetes. - : AMER DIABETES ASSOC. - 0012-1797 .- 1939-327X. ; 66:7, s. 2019-2032
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Journal article (peer-reviewed)abstract
- To identify novel coding association signals and facilitate characterization of mechanisms influencing glycemic traits and type 2 diabetes risk, we analyzed 109,215 variants derived from exome array genotyping together with an additional 390,225 variants from exome sequence in up to 39,339 normoglycemic individuals from five ancestry groups. We identified a novel association between the coding variant (p.Pro50Thr) in AKT2 and fasting plasma insulin (FI), a gene in which rare fully penetrant mutations are causal for monogenic glycemic disorders. The low-frequency allele is associated with a 12% increase in FI levels. This variant is present at 1.1% frequency in Finns but virtually absent in individuals from other ancestries. Carriers of the FI-increasing allele had increased 2-h insulin values, decreased insulin sensitivity, and increased risk of type 2 diabetes (odds ratio 1.05). In cellular studies, the AKT2-Thr50 protein exhibited a partial loss of function. We extend the allelic spectrum for coding variants in AKT2 associated with disorders of glucose homeostasis and demonstrate bidirectional effects of variants within the pleckstrin homology domain of AKT2.
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| 14. |
- Sawcer, Stephen, et al.
(author)
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Genetic risk and a primary role for cell-mediated immune mechanisms in multiple sclerosis
- 2011
-
In: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 476:7359, s. 214-219
-
Journal article (peer-reviewed)abstract
- Multiple sclerosis is a common disease of the central nervous system in which the interplay between inflammatory and neurodegenerative processes typically results in intermittent neurological disturbance followed by progressive accumulation of disability. Epidemiological studies have shown that genetic factors are primarily responsible for the substantially increased frequency of the disease seen in the relatives of affected individuals, and systematic attempts to identify linkage in multiplex families have confirmed that variation within the major histocompatibility complex (MHC) exerts the greatest individual effect on risk. Modestly powered genome-wide association studies (GWAS) have enabled more than 20 additional risk loci to be identified and have shown that multiple variants exerting modest individual effects have a key role in disease susceptibility. Most of the genetic architecture underlying susceptibility to the disease remains to be defined and is anticipated to require the analysis of sample sizes that are beyond the numbers currently available to individual research groups. In a collaborative GWAS involving 9,772 cases of European descent collected by 23 research groups working in 15 different countries, we have replicated almost all of the previously suggested associations and identified at least a further 29 novel susceptibility loci. Within the MHC we have refined the identity of the HLA-DRB1 risk alleles and confirmed that variation in the HLA-A gene underlies the independent protective effect attributable to the class I region. Immunologically relevant genes are significantly overrepresented among those mapping close to the identified loci and particularly implicate T-helper-cell differentiation in the pathogenesis of multiple sclerosis.
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| 15. |
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| 16. |
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| 17. |
- Capo, Eric, et al.
(author)
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A consensus protocol for the recovery of mercury methylation genes from metagenomes
- 2023
-
In: Molecular Ecology Resources. - : John Wiley & Sons. - 1755-098X .- 1755-0998. ; 23:1, s. 190-204
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Journal article (peer-reviewed)abstract
- Mercury (Hg) methylation genes (hgcAB) mediate the formation of the toxic methylmercury and have been identified from diverse environments, including freshwater and marine ecosystems, Arctic permafrost, forest and paddy soils, coal-ash amended sediments, chlor-alkali plants discharges and geothermal springs. Here we present the first attempt at a standardized protocol for the detection, identification and quantification of hgc genes from metagenomes. Our Hg-cycling microorganisms in aquatic and terrestrial ecosystems (Hg-MATE) database, a catalogue of hgc genes, provides the most accurate information to date on the taxonomic identity and functional/metabolic attributes of microorganisms responsible for Hg methylation in the environment. Furthermore, we introduce "marky-coco", a ready-to-use bioinformatic pipeline based on de novo single-metagenome assembly, for easy and accurate characterization of hgc genes from environmental samples. We compared the recovery of hgc genes from environmental metagenomes using the marky-coco pipeline with an approach based on coassembly of multiple metagenomes. Our data show similar efficiency in both approaches for most environments except those with high diversity (i.e., paddy soils) for which a coassembly approach was preferred. Finally, we discuss the definition of true hgc genes and methods to normalize hgc gene counts from metagenomes.
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| 18. |
- Düsterer, S., et al.
(author)
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Angle resolved photoelectron spectroscopy of two-color XUV-NIR ionization with polarization control
- 2016
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In: Journal of Physics B: Atomic, Molecular and Optical Physics. - : IOP Publishing. - 0953-4075 .- 1361-6455. ; 49:16
-
Journal article (peer-reviewed)abstract
- Electron emission caused by extreme ultraviolet (XUV) radiation in the presence of a strong near infrared (NIR) field leads to multiphoton interactions that depend on several parameters. Here, a comprehensive study of the influence of the angle between the polarization directions of the NIR and XUV fields on the two-color angle-resolved photoelectron spectra of He and Ne is presented. The resulting photoelectron angular distribution strongly depends on the orientation of the NIR polarization plane with respect to that of the XUV field. The prevailing influence of the intense NIR field over the angular emission characteristics for He(1s) and Ne(2p) ionization lines is shown. The underlying processes are modeled in the frame of the strong field approximation (SFA) which shows very consistent agreement with the experiment reaffirming the power of the SFA for multicolor-multiphoton ionization in this regime.
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| 19. |
- Kuchenbaecker, K, et al.
(author)
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The transferability of lipid loci across African, Asian and European cohorts
- 2019
-
In: Nature communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 10:1, s. 4330-
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Journal article (peer-reviewed)abstract
- Most genome-wide association studies are based on samples of European descent. We assess whether the genetic determinants of blood lipids, a major cardiovascular risk factor, are shared across populations. Genetic correlations for lipids between European-ancestry and Asian cohorts are not significantly different from 1. A genetic risk score based on LDL-cholesterol-associated loci has consistent effects on serum levels in samples from the UK, Uganda and Greece (r = 0.23–0.28, p < 1.9 × 10−14). Overall, there is evidence of reproducibility for ~75% of the major lipid loci from European discovery studies, except triglyceride loci in the Ugandan samples (10% of loci). Individual transferable loci are identified using trans-ethnic colocalization. Ten of fourteen loci not transferable to the Ugandan population have pleiotropic associations with BMI in Europeans; none of the transferable loci do. The non-transferable loci might affect lipids by modifying food intake in environments rich in certain nutrients, which suggests a potential role for gene-environment interactions.
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| 20. |
- Lutman, A. A., et al.
(author)
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Polarization control in an X-ray free-electron laser
- 2016
-
In: Nature Photonics. - : Springer Science and Business Media LLC. - 1749-4885 .- 1749-4893. ; 10:7, s. 468-472
-
Journal article (peer-reviewed)abstract
- X-ray free-electron lasers are unique sources of high-brightness coherent radiation. However, existing devices supply only linearly polarized light, precluding studies of chiral dynamics. A device called the Delta undulator has been installed at the Linac Coherent Light Source (LCLS) to provide tunable polarization. With a reverse tapered planar undulator line to pre-microbunch the beam and the novel technique of beam diverting, hundreds of microjoules of circularly polarized X-ray pulses are produced at 500-1,200 eV. These X-ray pulses are tens of femtoseconds long, have a degree of circular polarization of 0.98(+0.02)(-0.04) at 707 eV and may be scanned in energy. We also present a new two-colour X-ray pump-X-ray probe operating mode for the LCLS. Energy differences of Delta E/E = 2.4% are supported, and the second pulse can be adjusted to any elliptical polarization. In this mode, the pointing, timing, intensity and wavelength of the two pulses can be modified.
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| 21. |
- Mahajan, Anubha, et al.
(author)
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Identification and Functional Characterization of G6PC2 Coding Variants Influencing Glycemic Traits Define an Effector Transcript at the G6PC2-ABCB11 Locus.
- 2015
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In: PLoS Genetics. - : Public Library of Science (PLoS). - 1553-7404 .- 1553-7390. ; 11:1
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Journal article (peer-reviewed)abstract
- Genome wide association studies (GWAS) for fasting glucose (FG) and insulin (FI) have identified common variant signals which explain 4.8% and 1.2% of trait variance, respectively. It is hypothesized that low-frequency and rare variants could contribute substantially to unexplained genetic variance. To test this, we analyzed exome-array data from up to 33,231 non-diabetic individuals of European ancestry. We found exome-wide significant (P<5×10-7) evidence for two loci not previously highlighted by common variant GWAS: GLP1R (p.Ala316Thr, minor allele frequency (MAF)=1.5%) influencing FG levels, and URB2 (p.Glu594Val, MAF = 0.1%) influencing FI levels. Coding variant associations can highlight potential effector genes at (non-coding) GWAS signals. At the G6PC2/ABCB11 locus, we identified multiple coding variants in G6PC2 (p.Val219Leu, p.His177Tyr, and p.Tyr207Ser) influencing FG levels, conditionally independent of each other and the non-coding GWAS signal. In vitro assays demonstrate that these associated coding alleles result in reduced protein abundance via proteasomal degradation, establishing G6PC2 as an effector gene at this locus. Reconciliation of single-variant associations and functional effects was only possible when haplotype phase was considered. In contrast to earlier reports suggesting that, paradoxically, glucose-raising alleles at this locus are protective against type 2 diabetes (T2D), the p.Val219Leu G6PC2 variant displayed a modest but directionally consistent association with T2D risk. Coding variant associations for glycemic traits in GWAS signals highlight PCSK1, RREB1, and ZHX3 as likely effector transcripts. These coding variant association signals do not have a major impact on the trait variance explained, but they do provide valuable biological insights.
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| 22. |
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| 23. |
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| 24. |
- van de Munckhof, A., et al.
(author)
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Outcomes of Cerebral Venous Thrombosis due to Vaccine-Induced Immune Thrombotic Thrombocytopenia After the Acute Phase
- 2022
-
In: Stroke. - : Ovid Technologies (Wolters Kluwer Health). - 0039-2499 .- 1524-4628. ; 53:10, s. 3206-3210
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Journal article (peer-reviewed)abstract
- Background: Cerebral venous thrombosis (CVT) due to vaccine-induced immune thrombotic thrombocytopenia (VITT) is a severe condition, with high in-hospital mortality rates. Here, we report clinical outcomes of patients with CVT-VITT after SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) vaccination who survived initial hospitalization. Methods: We used data from an international registry of patients who developed CVT within 28 days of SARS-CoV-2 vaccination, collected until February 10, 2022. VITT diagnosis was classified based on the Pavord criteria. Outcomes were mortality, functional independence (modified Rankin Scale score 0-2), VITT relapse, new thrombosis, and bleeding events (all after discharge from initial hospitalization). Results: Of 107 CVT-VITT cases, 43 (40%) died during initial hospitalization. Of the remaining 64 patients, follow-up data were available for 60 (94%) patients (37 definite VITT, 9 probable VITT, and 14 possible VITT). Median age was 40 years and 45/60 (75%) patients were women. Median follow-up time was 150 days (interquartile range, 94-194). Two patients died during follow-up (3% [95% CI, 1%-11%). Functional independence was achieved by 53/60 (88% [95% CI, 78%-94%]) patients. No new venous or arterial thrombotic events were reported. One patient developed a major bleeding during follow-up (fatal intracerebral bleed). Conclusions: In contrast to the high mortality of CVT-VITT in the acute phase, mortality among patients who survived the initial hospitalization was low, new thrombotic events did not occur, and bleeding events were rare. Approximately 9 out of 10 CVT-VITT patients who survived the acute phase were functionally independent at follow-up.
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| 25. |
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| 26. |
- Beecham, Ashley H, et al.
(author)
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Analysis of immune-related loci identifies 48 new susceptibility variants for multiple sclerosis.
- 2013
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In: Nature genetics. - : Springer Science and Business Media LLC. - 1546-1718 .- 1061-4036. ; 45:11, s. 1353-60
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Journal article (peer-reviewed)abstract
- Using the ImmunoChip custom genotyping array, we analyzed 14,498 subjects with multiple sclerosis and 24,091 healthy controls for 161,311 autosomal variants and identified 135 potentially associated regions (P < 1.0 × 10(-4)). In a replication phase, we combined these data with previous genome-wide association study (GWAS) data from an independent 14,802 subjects with multiple sclerosis and 26,703 healthy controls. In these 80,094 individuals of European ancestry, we identified 48 new susceptibility variants (P < 5.0 × 10(-8)), 3 of which we found after conditioning on previously identified variants. Thus, there are now 110 established multiple sclerosis risk variants at 103 discrete loci outside of the major histocompatibility complex. With high-resolution Bayesian fine mapping, we identified five regions where one variant accounted for more than 50% of the posterior probability of association. This study enhances the catalog of multiple sclerosis risk variants and illustrates the value of fine mapping in the resolution of GWAS signals.
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| 27. |
- Bravo, Andrea G., et al.
(author)
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Methanogens and iron-reducing bacteria : the overlooked members of mercury-methylating microbial communities in boreal lakes
- 2018
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In: Applied and Environmental Microbiology. - : American Society for Microbiology. - 0099-2240 .- 1098-5336. ; 84:23
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Journal article (peer-reviewed)abstract
- ABSTRACT: Methylmercury is a potent human neurotoxin which biomagnifies in aquatic food webs. Although anaerobic microorganisms containing the hgcA gene potentially mediate the formation of methylmercury in natural environments, the diversity of these mercury-methylating microbial communities remains largely unexplored. Previous studies have implicated sulfate-reducing bacteria as the main mercury methylators in aquatic ecosystems. In the present study, we characterized the diversity of mercury-methylating microbial communities of boreal lake sediments using high-throughput sequencing of 16S rRNA and hgcA genes. Our results show that in the lake sediments, Methanomicrobiales and Geobacteraceae also represent abundant members of the mercury-methylating communities. In fact, incubation experiments with a mercury isotopic tracer and molybdate revealed that only between 38% and 45% of mercury methylation was attributed to sulfate reduction. These results suggest that methanogens and iron-reducing bacteria may contribute to more than half of the mercury methylation in boreal lakes.IMPORTANCE: Despite the global awareness that mercury, and methylmercury in particular, is a neurotoxin to which millions of people continue to be exposed, there are sizable gaps in the understanding of the processes and organisms involved in methylmercury formation in aquatic ecosystems. In the present study, we shed light on the diversity of the microorganisms responsible for methylmercury formation in boreal lake sediments. All the microorganisms identified are associated with the processing of organic matter in aquatic systems. Moreover, our results show that the well-known mercury-methylating sulfate-reducing bacteria constituted only a minor portion of the potential mercury methylators. In contrast, methanogens and iron-reducing bacteria were important contributors to methylmercury formation, highlighting their role in mercury cycling in the environment.
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| 28. |
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| 29. |
- Buck, Harleah G., et al.
(author)
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A systematic review of heart failure dyadic self-care interventions focusing on intervention components, contexts, and outcomes
- 2018
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In: International Journal of Nursing Studies. - : PERGAMON-ELSEVIER SCIENCE LTD. - 0020-7489 .- 1873-491X. ; 77, s. 232-242
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Research review (peer-reviewed)abstract
- Background: Having support from an informal carer is important for heart failure patients. Carers have the potential to improve patient self-care. At the same time, it should be acknowledged that caregiving could affect the carer negatively and cause emotional reactions of burden and stress. Dyadic (patient and informal carer) heart failure self-care interventions seek to improve patient self-care such as adherence to medical treatment, exercise training, symptom monitoring and symptom management when needed. Currently, no systematic assessment of dyadic interventions has been conducted with a focus on describing components, examining physical and delivery contexts, or determining the effect on patient and/or carer outcomes. Objective: To examine the components, context, and outcomes of dyadic self-care interventions. Design: A systematic review registered in PROSPERO, following PRISMA guidelines with a narrative analysis and realist synthesis. Data Sources: PubMed, EMBASE, Web of Science, PsycINFO, and Cochrane Central Register of Controlled Trials were searched using MeSH, EMTREE terms, keywords, and keyword phrases for the following concepts: dyadic, carers, heart failure and intervention. Eligible studies were original research, written in English, on dyadic self-care interventions in adult samples. Review methods: We used a two-tiered analytic approach including both completed studies with power to determine outcomes and ongoing studies including abstracts, small pilot studies and protocols to forecast future directions. Results: Eighteen papers - 12 unique, completed intervention studies (two quasi- and ten experimental trials) from 2000 to 2016 were reviewed. Intervention components fell into three groups education, support, and guidance. Interventions were implemented in 5 countries, across multiple settings of care, and involved 3 delivery modes face to face, telephone or technology based. Dyadic intervention effects on cognitive, behavioral, affective and health services utilization outcomes were found within studies. However, findings across studies were inconclusive as some studies reported positive and some non-sustaining outcomes on the same variables. All the included papers had methodological limitations including insufficient sample size, mixed intervention effects and counter-intuitive outcomes. Conclusions: We found that the evidence from dyadic interventions to promote heart failure self-care, while growing, is still very limited. Future research needs to involve advanced sample size justification, innovative solutions to increase and sustain behavior change, and use of mixed methods for capturing a more holistic picture of effects in clinical practice.
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| 30. |
- Buder, Sven, et al.
(author)
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The GALAH plus survey : Third data release
- 2021
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In: Monthly notices of the Royal Astronomical Society. - : Oxford University Press. - 0035-8711 .- 1365-2966. ; 506:1, s. 150-201
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Journal article (peer-reviewed)abstract
- The ensemble of chemical element abundance measurements for stars, along with precision distances and orbit properties, provides high-dimensional data to study the evolution of the Milky Way. With this third data release of the Galactic Archaeology with HERMES (GALAH) survey, we publish 678 423 spectra for 588 571 mostly nearby stars (81.2 per cent of stars are within <2 kpc), observed with the HERMES spectrograph at the Anglo-Australian Telescope. This release (hereafter GALAH+ DR3) includes all observations from GALAH Phase 1 (bright, main, and faint survey, 70 per cent), K2-HERMES (17 per cent), TESS-HERMES (5 per cent), and a subset of ancillary observations (8 per cent) including the bulge and >75 stellar clusters. We derive stellar parameters T-eff, logg, [Fe/H], v(mic), v(broad), and v(rad) using our modified version of the spectrum synthesis code Spectroscopy Made Easy (SME) and 1D MARCS model atmospheres. We break spectroscopic degeneracies in our spectrum analysis with astrometry from Gaia DR2 and photometry from 2MASS. We report abundance ratios [X/Fe] for 30 different elements (11 of which are based on non-LTE computations) covering five nucleosynthetic pathways. We describe validations for accuracy and precision, flagging of peculiar stars/measurements and recommendations for using our results. Our catalogue comprises 65 per cent dwarfs, 34 per cent giants, and 1 per cent other/unclassified stars. Based on unflagged chemical composition and age, we find 62 per cent young low-alpha, 9 per cent young high-alpha, 27 per cent old high-alpha, and 2 per cent stars with [Fe/H] <= -1. Based on kinematics, 4 per cent are halo stars. Several Value-Added-Catalogues, including stellar ages and dynamics, updated after Gaia eDR3, accompany this release and allow chrono-chemodynamic analyses, as we showcase.
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| 31. |
- Buder, Sven, et al.
(author)
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The GALAH+ survey : Third data release
- 2021
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In: Monthly notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 506:1, s. 150-201
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Journal article (peer-reviewed)abstract
- The ensemble of chemical element abundance measurements for stars, along with precision distances and orbit properties, provides high-dimensional data to study the evolution of the Milky Way. With this third data release of the Galactic Archaeology with HERMES (GALAH) survey, we publish 678 423 spectra for 588 571 mostly nearby stars (81.2 per cent of stars are within <2 kpc), observed with the HERMES spectrograph at the Anglo-Australian Telescope. This release (hereafter GALAH+ DR3) includes all observations from GALAH Phase 1 (bright, main, and faint survey, 70 per cent), K2-HERMES (17 per cent), TESS-HERMES (5 per cent), and a subset of ancillary observations (8 per cent) including the bulge and >75 stellar clusters. We derive stellar parameters Teff, log g, [Fe/H], vmic, vbroad, and vrad using our modified version of the spectrum synthesis code Spectroscopy Made Easy (sme) and 1D marcs model atmospheres. We break spectroscopic degeneracies in our spectrum analysis with astrometry from Gaia DR2 and photometry from 2MASS. We report abundance ratios [X/Fe] for 30 different elements (11 of which are based on non-LTE computations) covering five nucleosynthetic pathways. We describe validations for accuracy and precision, flagging of peculiar stars/measurements and recommendations for using our results. Our catalogue comprises 65 per cent dwarfs, 34 per cent giants, and 1 per cent other/unclassified stars. Based on unflagged chemical composition and age, we find 62 per cent young low-α, 9 per cent young high-α, 27 per cent old high-α, and 2 per cent stars with [Fe/H] ≤ −1. Based on kinematics, 4 per cent are halo stars. Several Value-Added-Catalogues, including stellar ages and dynamics, updated after Gaia eDR3, accompany this release and allow chrono-chemodynamic analyses, as we showcase.
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| 32. |
- Buder, Sven, et al.
(author)
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The GALAH Survey : chemical tagging and chrono-chemodynamics of accreted halo stars with GALAH+DR3 and Gaia eDR3
- 2022
-
In: Monthly notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 510:2, s. 2407-2436
-
Journal article (peer-reviewed)abstract
- Since the advent of Gaia astrometry, it is possible to identify massive accreted systems within the Galaxy through their unique dynamical signatures. One such system, Gaia-Sausage-Enceladus (GSE), appears to be an early ‘building block’ given its virial mass >1010M⊙ at infall (z ∼ 1−3). In order to separate the progenitor population from the background stars, we investigate its chemical properties with up to 30 element abundances from the GALAH+ Survey Data Release 3 (DR3). To inform our choice of elements for purely chemically selecting accreted stars, we analyse 4164 stars with low-α abundances and halo kinematics. These are most different to the Milky Way stars for abundances of Mg, Si, Na, Al, Mn, Fe, Ni, and Cu. Based on the significance of abundance differences and detection rates, we apply Gaussian mixture models to various element abundance combinations. We find the most populated and least contaminated component, which we confirm to represent GSE, contains 1049 stars selected via [Na/Fe] versus [Mg/Mn] in GALAH+ DR3. We provide tables of our selections and report the chrono-chemodynamical properties (age, chemistry, and dynamics). Through a previously reported clean dynamical selection of GSE stars, including 30<√JR/kpckms−1<55, we can characterize an unprecedented 24 abundances of this structure with GALAH+ DR3. With our chemical selection we characterize the dynamical properties of the GSE, for example mean √JR/kpckms−1=26+9−14. We find only (29±1) per cent of the GSE stars within the clean dynamical selection region. Our methodology will improve future studies of accreted structures and their importance for the formation of the Milky Way.
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| 33. |
- Buerger, M., et al.
(author)
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Coolability of particulate beds in severe accidents : Status and remaining uncertainties
- 2010
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In: Progress in nuclear energy (New series). - : Elsevier BV. - 0149-1970 .- 1878-4224. ; 52:1, s. 61-75
-
Journal article (peer-reviewed)abstract
- Particulate debris beds may form during different stages of a severe core melt accident; e.g. in the degrading hot core, due to thermal stresses during reflooding, in the lower plenum, by melt flow from the core into water in the lower head, and in the cavity by melt flow out of a failing RPV into a wet cavity. Deep water pools in the cavity are used in Nordic BWRs as an accident management measure aiming at particulate debris formation and coolability. It has been elaborated in the joint work of the European Severe Accident Research Network (SARNET) in Work Package (WP) 11.1 that coolability of particulate debris, reflooding of hot debris as well as boil-off under decay heat (long-term coolability), is strongly favoured by 2D/3D effects in beds with non-homogeneous structure and shape. Especially, water inflow from the sides and via bottom regions strongly improves coolability as compared to 1D situations with top flooding, the latter being in the past the basis of analyses on coolability. Data from experiments included in the SARNET network (DEBRIS at IKE and STYX at VTT) and earlier ones (e.g. POMECO at KTH) have been used to validate key constitutive laws in 2D codes as WABE (IKE) and ICARE/CATHARE (IRSN), especially concerning flow friction and heat transfer. Major questions concern the need of the explicit use of interfacial friction to adequately treat the various flow situations in a unified approach, as well as the adequate characterization of realistic debris composed of irregularly shaped particles of different sizes. joint work has been supported by transfer of the WABE code to KTH and VTT. Concerning realistic debris, the formation from breakup of melt jets in water is investigated in the DEFOR experiments at KTH. Present results indicate that porosities in the debris might be much higher than previously assumed, which would strongly support attainment of coolability. Calculations have been performed with IKEJET/IKEMIX describing jet breakup, mixing and settling of resulting particles. Models about debris bed formation and porosity are developed at KTH. The codes have been applied to reactor conditions for analysing the potential for coolability in the different phases of a severe accident. Calculations have been performed with WABE (MEWA) implemented in ATHLET-CD and with ICARE/ICATHARE for degraded cores and debris beds in the lower plenum, under reflooding and boil-off. Ex-vessel situations have also been analysed. Strong effects of lateral water inflow and cooling by steam in hot areas have been demonstrated. In support, some typical basic configurations have been analysed, e.g. configurations with downcomers considered as possible AM measures. Melt pool formation or coolability of particulate debris is a major issue concerning melt retention in the core and the lower head. Present conclusions from those analyses for adequate modelling in ASTEC are outlined as well as remaining uncertainties. Experimental and analysis efforts and respective continued joint actions are discussed, which are needed to reach resolution of the coolability issue.
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| 34. |
- Capo, Eric, et al.
(author)
-
Deltaproteobacteria andSpirochaetes-Like Bacteria AreAbundant Putative MercuryMethylators in Oxygen-DeficientWater and Marine Particles in theBaltic Sea
- 2020
-
In: Frontiers in Microbiology. - : Frontiers Media SA. - 1664-302X. ; , s. 1-11
-
Journal article (peer-reviewed)abstract
- Methylmercury (MeHg), a neurotoxic compound biomagnifying in aquatic food webs, can be a threat to human health via fish consumption. However, the compositionand distribution of the microbial communities mediating the methylation of mercury (Hg) to MeHg in marine systems remain largely unknown. In order to fill this knowledge gap, we used the Baltic Sea Reference Metagenome (BARM) dataset to study the abundance and distribution of the genes involved in Hg methylation (the hgcAB gene cluster). We determined the relative abundance of the hgcAB genes and their taxonomic identity in 81 brackish metagenomes that cover spatial,seasonal and redox variability in the Baltic Sea water column. The hgcAB genes were predominantly detected in anoxic water, but some hgcAB genes were alsodetected in hypoxic and normoxic waters. Phylogenetic analysis identified putative Hg methylators within Deltaproteobacteria, in oxygen-deficient water layers, but also Spirochaetes-like and Kiritimatiellaeota-like bacteria. Higher relative quantities of hgcAB genes were found in metagenomes from marine particles compared to free-living communities in anoxic water, suggesting that such particles are hotspot habitats for Hg methylators in oxygen-depleted seawater. Altogether, our work unveils the diversityof the microorganisms with the potential to mediate MeHg production in the BalticSea and pinpoint the important ecological niches for these microorganisms within themarine water column.
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| 35. |
- Capo, Eric, et al.
(author)
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Expression Levels of hgcAB Genes and Mercury Availability Jointly Explain Methylmercury Formation in Stratified Brackish Waters
- 2022
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In: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 56:18, s. 13119-13130
-
Journal article (peer-reviewed)abstract
- Neurotoxic methylmercury (MeHg) is formed by microbial methylation of inorganic divalent Hg (Hg-II) and constitutes severe environmental and human health risks. The methylation is enabled by hgcA and hgcB genes, but it is not know nif the associated molecular-level processes are rate-limiting or enable accurate prediction of MeHg formation in nature. In this study, we investigated the relationships between hgc genes and MeHg across redox-stratified water columns in the brackish Baltic Sea. We showed, for the first time, that hgc transcript abundance and the concentration of dissolved Hg-II-sulfide species were strong predictors of both the Hg-II methylation rate and MeHg concentration, implying their roles as principal joint drivers of MeHg formation in these systems. Additionally, we characterized the metabolic capacities of hgc(+) microorganisms by reconstructing their genomes from metagenomes (i.e., hgc(+) MAGs), which highlighted the versatility of putative Hg-II methylators in the water column of the Baltic Sea. In establishing relationships between hgc transcripts and the Hg-II methylation rate, we advance the fundamental understanding of mechanistic principles governing MeHg formation in nature and enable refined predictions of MeHg levels in coastal seas in response to the accelerating spread of oxygen-deficientzones.
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| 36. |
- Capo, Eric, et al.
(author)
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Oxygen-deficient water zones in the Baltic Sea promote uncharacterized Hg methylating microorganisms in underlying sediments
- 2022
-
In: Limnology and Oceanography. - : Wiley. - 1939-5590 .- 0024-3590. ; 67:1, s. 135-146
-
Journal article (peer-reviewed)abstract
- Human-induced expansion of oxygen-deficient zones can have dramatic impacts on marine systems and its resident biota. One example is the formation of the potent neurotoxic methylmercury (MeHg) that is mediated by microbial methylation of inorganic divalent Hg (HgII) under oxygen-deficient conditions. A negative consequence of the expansion of oxygen-deficient zones could be an increase in MeHg production due to shifts in microbial communities in favor of microorganisms methylating Hg. There is, however, limited knowledge about Hg-methylating microbes, i.e., those carrying hgc genes critical for mediating the process, from marine sediments. Here, we aim to study the presence of hgc genes and transcripts in metagenomes and metatranscriptomes from four surface sediments with contrasting concentrations of oxygen and sulfide in the Baltic Sea. We show that potential Hg methylators differed among sediments depending on redox conditions. Sediments with an oxygenated surface featured hgc-like genes and transcripts predominantly associated with uncultured Desulfobacterota (OalgD group) and Desulfobacterales (including Desulfobacula sp.) while sediments with a hypoxic-anoxic surface included hgc-carrying Verrucomicrobia, unclassified Desulfobacterales, Desulfatiglandales, and uncharacterized microbes. Our data suggest that the expansion of oxygen-deficient zones in marine systems may lead to a compositional change of Hg-methylating microbial groups in the sediments, where Hg methylators whose metabolism and biology have not yet been characterized will be promoted and expand.
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| 37. |
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| 38. |
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| 39. |
- Dionne-Odom, J. Nicholas, et al.
(author)
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Family caregiving for persons with heart failure at the intersection of heart failure and palliative care: a state-of-the-science review
- 2017
-
In: Heart Failure Reviews. - : SPRINGER. - 1382-4147 .- 1573-7322. ; 22:5, s. 543-557
-
Research review (peer-reviewed)abstract
- Many of the 23 million individuals with heart failure (HF) worldwide receive daily, unpaid support from a family member or friend. Although HF and palliative care practice guidelines stipulate that support be provided to family caregivers, the evidence base to guide care for this population has not been comprehensively assessed. In order to appraise the state-of-the-science of HF family caregiving and recommend areas for future research, the aims of this review were to summarize (1) how caregivers influence patients, (2) the consequences of HF for caregivers, and (3) interventions directed at HF caregivers. We reviewed all literature to December 2015 in PubMed and CINAHL using the search terms "heart failure" AND "caregiver." Inclusion criteria dictated that studies report original research of HF family caregiving. Articles focused on children or instrument development or aggregated HF with other illnesses were excluded. We identified 120 studies, representing 5700 caregivers. Research on this population indicates that (1) caregiving situations vary widely with equally wide-ranging tasks for patients to help facilitate their health behaviors, psychological health and relationships, and quality of life (QoL); (2) caregivers have numerous unmet needs that fluctuate with patients unpredictable medical status, are felt to be ignored by the formal healthcare system, and can lead to distress, burden, and reduced QoL; and (3) relatively few interventions have been developed and tested that effectively support HF family caregivers. We provide recommendations to progress the science forward in each of these areas that moves beyond descriptive work to intervention development and clinical trials testing.
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| 40. |
- Donis, Daphne, et al.
(author)
-
Stratification strength and light climate explain variation in chlorophyll a at the continental scale in a European multilake survey in a heatwave summer
- 2021
-
In: Limnology and Oceanography. - : John Wiley & Sons. - 0024-3590 .- 1939-5590. ; 66:12, s. 4314-4333
-
Journal article (peer-reviewed)abstract
- To determine the drivers of phytoplankton biomass, we collected standardized morphometric, physical, and biological data in 230 lakes across the Mediterranean, Continental, and Boreal climatic zones of the European continent. Multilinear regression models tested on this snapshot of mostly eutrophic lakes (median total phosphorus [TP] = 0.06 and total nitrogen [TN] = 0.7 mg L-1), and its subsets (2 depth types and 3 climatic zones), show that light climate and stratification strength were the most significant explanatory variables for chlorophyll a (Chl a) variance. TN was a significant predictor for phytoplankton biomass for shallow and continental lakes, while TP never appeared as an explanatory variable, suggesting that under high TP, light, which partially controls stratification strength, becomes limiting for phytoplankton development. Mediterranean lakes were the warmest yet most weakly stratified and had significantly less Chl a than Boreal lakes, where the temperature anomaly from the long-term average, during a summer heatwave was the highest (+4 degrees C) and showed a significant, exponential relationship with stratification strength. This European survey represents a summer snapshot of phytoplankton biomass and its drivers, and lends support that light and stratification metrics, which are both affected by climate change, are better predictors for phytoplankton biomass in nutrient-rich lakes than nutrient concentrations and surface temperature.
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| 41. |
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| 42. |
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| 43. |
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| 44. |
- Götzfried, J., et al.
(author)
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Physics of High-Charge Electron Beams in Laser-Plasma Wakefields
- 2020
-
In: Physical Review X. - : American Physical Society. - 2160-3308. ; 10:4
-
Journal article (peer-reviewed)abstract
- Laser wakefield acceleration (LWFA) and its particle-driven counterpart, particle or plasma wakefield acceleration (PWFA), are commonly treated as separate, though related, branches of high-gradient plasma-based acceleration. However, novel proposed schemes are increasingly residing at the interface of both concepts where the understanding of their interplay becomes crucial. Here, we present a comprehensive study of this regime, which we may term laser-plasma wakefields. Using datasets of hundreds of shots, we demonstrate the influence of beam loading on the spectral shape of electron bunches. Similar results are obtained using both 100-TW-class and few-cycle lasers, highlighting the scale invariance of the involved physical processes. Furthermore, we probe the interplay of dual electron bunches in the same or in two subsequent plasma periods under the influence of beam loading. We show that, with decreasing laser intensity, beam loading transitions to a beam-dominated regime, where the first bunch acts as the main driver of the wakefield. This transition is evidenced experimentally by a varying acceleration of a low-energy witness beam with respect to the charge of a high-energy drive beam in a spatially separate gas target. Our results also present an important step in the development of LWFA using controlled injection in a shock front. The electron beams in this study reach record performance in terms of laser-to-beam energy transfer efficiency (up to 10%), spectral charge density (regularly exceeding 10 pC MeV−1), and angular charge density (beyond 300 pC μsr−1 at 220 MeV). We provide an experimental scaling for the accelerated charge per terawatt (TW) of laser power, which approaches 2 nC at 300 TW. With the expanding availability of petawatt-class (PW) lasers, these beam parameters will become widely accessible. Thus, the physics of laser-plasma wakefields is expected to become increasingly relevant, as it provides new paths toward low-emittance beam generation for future plasma-based colliders or light sources.
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| 45. |
- Hartmann, G., et al.
(author)
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Circular dichroism measurements at an x-ray free-electron laser with polarization control
- 2016
-
In: Review of Scientific Instruments. - : AIP Publishing. - 0034-6748 .- 1089-7623. ; 87:8
-
Journal article (peer-reviewed)abstract
- A non-destructive diagnostic method for the characterization of circularly polarized, ultraintense, short wavelength free-electron laser (FEL) light is presented. The recently installed Delta undulator at the LCLS (Linac Coherent Light Source) at SLAC National Accelerator Laboratory (USA) was used as showcase for this diagnostic scheme. By applying a combined two-color, multi-photon experiment with polarization control, the degree of circular polarization of the Delta undulator has been determined. Towards this goal, an oriented electronic state in the continuum was created by non-resonant ionization of the O2 1s core shell with circularly polarized FEL pulses at hν 700 eV. An also circularly polarized, highly intense UV laser pulse with hν 3.1 eV was temporally and spatially overlapped, causing the photoelectrons to redistribute into so-called sidebands that are energetically separated by the photon energy of the UV laser. By determining the circular dichroism of these redistributed electrons using angle resolving electron spectroscopy and modeling the results with the strong-field approximation, this scheme allows to unambiguously determine the absolute degree of circular polarization of any pulsed, ultraintense XUV or X-ray laser source. © 2016 Author(s).
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| 46. |
- Hartmann, N., et al.
(author)
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Attosecond time-energy structure of X-ray free-electron laser pulses
- 2018
-
In: Nature Photonics. - : Springer Science and Business Media LLC. - 1749-4885 .- 1749-4893. ; 12:4, s. 215-220
-
Journal article (peer-reviewed)abstract
- The time-energy information of ultrashort X-ray free-electron laser pulses generated by the Linac Coherent Light Source is measured with attosecond resolution via angular streaking of neon 1s photoelectrons. The X-ray pulses promote electrons from the neon core level into an ionization continuum, where they are dressed with the electric field of a circularly polarized infrared laser. This induces characteristic modulations of the resulting photoelectron energy and angular distribution. From these modulations we recover the single-shot attosecond intensity structure and chirp of arbitrary X-ray pulses based on self-amplified spontaneous emission, which have eluded direct measurement so far. We characterize individual attosecond pulses, including their instantaneous frequency, and identify double pulses with well-defined delays and spectral properties, thus paving the way for X-ray pump/X-ray probe attosecond free-electron laser science. © 2018 The Author(s).
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| 47. |
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| 48. |
- Heider, R., et al.
(author)
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Megahertz-compatible angular streaking with few-femtosecond resolution at x-ray free-electron lasers
- 2019
-
In: Physical Review A. - 2469-9926. ; 100:5
-
Journal article (peer-reviewed)abstract
- Highly brilliant, coherent, femtosecond x-ray pulses delivered by free-electron lasers (FELs) constitute one of the pillars of modern ultrafast science. Next generation FEL facilities provide up to megahertz repetition rates and pulse durations down to the attosecond regime utilizing self-amplification of spontaneous emission. However, the stochastic nature of this generation mechanism demands single-shot pulse characterization to perform meaningful experiments. Here we demonstrate a fast yet robust online analysis technique capable of megahertz-rate mapping of the temporal intensity structure and arrival time of x-ray FEL pulses with few-femtosecond resolution. We performed angular streaking measurements of both neon photo- and Auger electrons and show their applicability for a direct time-domain feedback system during ongoing experiments. The fidelity of the real-time pulse characterization algorithm is corroborated by resolving isolated x-ray pulses and double pulse trains with few-femtosecond substructure, thus paving the way for x-ray-pump-x-ray-probe FEL science at repetition rates compatible with the demands of LCLS-II and European XFEL.
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| 49. |
- Herp, Simone, et al.
(author)
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Mucispirillum schaedleri Antagonizes Salmonella Virulence to Protect Mice against Colitis
- 2019
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In: Cell Host and Microbe. - : Elsevier BV. - 1931-3128 .- 1934-6069. ; 25:5, s. 681-694.e8
-
Journal article (peer-reviewed)abstract
- The microbiota and the gastrointestinal mucus layer play a pivotal role in protection against non-typhoidal Salmonella enterica serovar Typhimurium (S. Tm) colitis. Here, we analyzed the course of Salmonella colitis in mice lacking a functional mucus layer in the gut. Unexpectedly, in contrast to mucus-proficient littermates, genetically deficient mice were protected against Salmonellainduced gut inflammation in the streptomycin colitis model. This correlated with microbiota alterations and enrichment of the bacterial phylum Deferribacteres. Using gnotobiotic mice associated with defined bacterial consortia, we causally linked Mucispirillum schaedleri, currently the sole known representative of Deferribacteres present in the mammalian microbiota, to host protection against S. Tm colitis. Inhibition by M. schaedleri involves interference with S. Tm invasion gene expression, partly by competing for anaerobic electron acceptors. In conclusion, this study establishes M. schaedleri, a core member of the murine gut microbiota, as a key antagonist of S. Tm virulence in the gut.
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| 50. |
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