Diverse methylotrophic methanogenic archaea cause high methane emissions from seagrass meadows

© The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Schorn, S., Ahmerkamp, S., Bullock, E., Weber, M., Lott, C., Liebeke, M., Lavik, G., Kuypers, M. M. M., Graf, J. S., & Milucka, J. Diverse methylotrophic methanogenic archaea cause high methane emissions from seagrass meadows. Proceedings of the National Academy of Sciences of the United States of America, 119(9), (2022): e2106628119, https://doi.org/10.1073/pnas.2106628119.Marine coastlines colonized by seagrasses are a net source of methane to the atmosphere. However, methane emissions from these environments are still poorly constrained, and the underlying processes and responsible microorganisms remain largely unknown. Here, we investigated methane turnover in seagrass meadows of Posidonia oceanica in the Mediterranean Sea. The underlying sediments exhibited median net fluxes of methane into the water column of ca. 106 µmol CH4 ⋅ m−2 ⋅ d−1. Our data show that this methane production was sustained by methylated compounds produced by the plant, rather than by fermentation of buried organic carbon. Interestingly, methane production was maintained long after the living plant died off, likely due to the persistence of methylated compounds, such as choline, betaines, and dimethylsulfoniopropionate, in detached plant leaves and rhizomes. We recovered multiple mcrA gene sequences, encoding for methyl-coenzyme M reductase (Mcr), the key methanogenic enzyme, from the seagrass sediments. Most retrieved mcrA gene sequences were affiliated with a clade of divergent Mcr and belonged to the uncultured Candidatus Helarchaeota of the Asgard superphylum, suggesting a possible involvement of these divergent Mcr in methane metabolism. Taken together, our findings identify the mechanisms controlling methane emissions from these important blue carbon ecosystems.This project was funded by theMax Planck Society

Edge states and determination of pairing symmetry in superconducting Sr2RuO4

We calculate the energy dispersion of the surface Andreev states and their contribution to tunneling conductance for the order parameters with horizontal and vertical lines of nodes proposed for superconducting Sr2RuO4. For vertical lines, we find double peaks in tunneling spectra reflecting the van Hove singularities in the density of surface states originating from the turning points in their energy dispersion. For horizontal lines, we find a single cusp-like peak at zero bias, which agrees very well with the experimental data on tunneling in Sr2RuO4.Comment: 6 pages, 6 figures. V.2: comparison with experiment added and discussion of horizontal nodes expanded. v.3: significant expansion: 1 figure and 2 pages added. v.4: acknowledgements added. Additional viewgraphs with experimental and theoretical curves superimposed are available at http://www2.physics.umd.edu/~yakovenk/talks/Sr2RuO4

The External Genitalia Score (EGS): A European Multicenter Validation Study

CONTEXT: Standardized description of external genitalia is needed in the assessment of children with atypical genitalia. OBJECTIVES: To validate the External Genitalia Score (EGS), to present reference values for preterm and term babies up to 24 months and correlate obtained scores with anogenital distances (AGDs). DESIGN, SETTING: A European multicenter (n = 8) validation study was conducted from July 2016 to July 2018. PATIENTS AND METHODS: EGS is based on the external masculinization score but uses a gradual scale from female to male (range, 0-12) and terminology appropriate for both sexes. The reliability of EGS and AGDs was determined by the interclass correlation coefficient (ICC). Cross-sectional data were obtained in 686 term babies (0-24 months) and 181 preterm babies, and 111 babies with atypical genitalia. RESULTS: The ICC of EGS in typical and atypical genitalia is excellent and good, respectively. Median EGS (10th to 90th centile) in males < 28 weeks gestation is 10 (8.6-11.5); in males 28-32 weeks 11.5 (9.2-12); in males 33-36 weeks 11.5 (10.5-12) and in full-term males 12 (10.5-12). In all female babies, EGS is 0 (0-0). The mean (SD) lower/upper AGD ratio (AGDl/u) is 0.45 (0.1), with significant difference between AGDl/u in males 0.49 (0.1) and females 0.39 (0.1) and intermediate values in differences of sex development (DSDs) 0.43 (0.1). The AGDl/u correlates with EGS in males with typical genitalia and in atypical genitalia. CONCLUSIONS: EGS is a reliable and valid tool to describe external genitalia in premature and term babies up to 24 months. EGS correlates with AGDl/u in males. It facilitates standardized assessment, clinical decision-making and multicenter research

The Long-Baseline Neutrino Experiment: Exploring Fundamental Symmetries of the Universe

The preponderance of matter over antimatter in the early Universe, the dynamics of the supernova bursts that produced the heavy elements necessary for life and whether protons eventually decay --- these mysteries at the forefront of particle physics and astrophysics are key to understanding the early evolution of our Universe, its current state and its eventual fate. The Long-Baseline Neutrino Experiment (LBNE) represents an extensively developed plan for a world-class experiment dedicated to addressing these questions. LBNE is conceived around three central components: (1) a new, high-intensity neutrino source generated from a megawatt-class proton accelerator at Fermi National Accelerator Laboratory, (2) a near neutrino detector just downstream of the source, and (3) a massive liquid argon time-projection chamber deployed as a far detector deep underground at the Sanford Underground Research Facility. This facility, located at the site of the former Homestake Mine in Lead, South Dakota, is approximately 1,300 km from the neutrino source at Fermilab -- a distance (baseline) that delivers optimal sensitivity to neutrino charge-parity symmetry violation and mass ordering effects. This ambitious yet cost-effective design incorporates scalability and flexibility and can accommodate a variety of upgrades and contributions. With its exceptional combination of experimental configuration, technical capabilities, and potential for transformative discoveries, LBNE promises to be a vital facility for the field of particle physics worldwide, providing physicists from around the globe with opportunities to collaborate in a twenty to thirty year program of exciting science. In this document we provide a comprehensive overview of LBNE's scientific objectives, its place in the landscape of neutrino physics worldwide, the technologies it will incorporate and the capabilities it will possess.Comment: Major update of previous version. This is the reference document for LBNE science program and current status. Chapters 1, 3, and 9 provide a comprehensive overview of LBNE's scientific objectives, its place in the landscape of neutrino physics worldwide, the technologies it will incorporate and the capabilities it will possess. 288 pages, 116 figure

Design Parameters to Control Synthetic Gene Expression in Escherichia coli

BACKGROUND:Production of proteins as therapeutic agents, research reagents and molecular tools frequently depends on expression in heterologous hosts. Synthetic genes are increasingly used for protein production because sequence information is easier to obtain than the corresponding physical DNA. Protein-coding sequences are commonly re-designed to enhance expression, but there are no experimentally supported design principles. PRINCIPAL FINDINGS:To identify sequence features that affect protein expression we synthesized and expressed in E. coli two sets of 40 genes encoding two commercially valuable proteins, a DNA polymerase and a single chain antibody. Genes differing only in synonymous codon usage expressed protein at levels ranging from undetectable to 30% of cellular protein. Using partial least squares regression we tested the correlation of protein production levels with parameters that have been reported to affect expression. We found that the amount of protein produced in E. coli was strongly dependent on the codons used to encode a subset of amino acids. Favorable codons were predominantly those read by tRNAs that are most highly charged during amino acid starvation, not codons that are most abundant in highly expressed E. coli proteins. Finally we confirmed the validity of our models by designing, synthesizing and testing new genes using codon biases predicted to perform well. CONCLUSION:The systematic analysis of gene design parameters shown in this study has allowed us to identify codon usage within a gene as a critical determinant of achievable protein expression levels in E. coli. We propose a biochemical basis for this, as well as design algorithms to ensure high protein production from synthetic genes. Replication of this methodology should allow similar design algorithms to be empirically derived for any expression system

How does neopatrimonialism affect the African state? The case of tax collection in Zambia

Following the neopatrimonialism paradigm, it can be hypothesised that in African states informal politics of the rulers infringe on the collection of taxes and in turn reduce state revenue. This article tests this proposition for the case of Zambia. Neopatrimonial continuity in the country is evidenced by three factors : the concentration of political power, the award of personal favours, and the misuse of state resources. Despite this continuity, the revenue performance increased considerably with the creation of the semi-autonomous Zambia Revenue Authority. Donor pressure has been the most important intervening variable accounting for this improvement. Yet, strengthening the collection of central state revenue has been consistent with a neopatrimonial rationale, and may even have fed neopatrimonialism overall, by providing increased resources for particularistic expenditure

Legitimacy intermediation in the multilevel European polity and its collapse in the euro crisis

This essay re-examines the dual – republican and liberal – foundations of democratic legitimacy in the Western traditions of normative political theory. Considered in isolation, the European Union conforms to liberal standards but cannot satisfy republican criteria. Given these conflicting standards, debates on the alleged European democratic deficit have remained inconclusive. Moreover, they have failed to pay sufficient attention to the multilevel character of the European polity and to the normative potential of legitimacy intermediation in its two-step compliance and legitimating relationships. I argue, however, that the capacity of democratic member states to legitimate the exercise of European governing functions is being destroyed in the present euro crisis, and I briefly discuss the implications of this new constellation.In der westlichen Tradition der normativen politischen Theorie beruht demokratische Legitimität auf der doppelten Grundlage republikanischer und liberaler Prinzipien. Für sich betrachtet entspricht die Europäische Union zwar liberalen Kriterien, aber eben nicht den republikanischen Anforderungen. Angesichts so unterschiedlicher Kriterien konnte es auch im Streit über das angebliche europäische Demokratiedefizit keine Einigung geben. Überdies ignorierte diese Diskussion den Mehrebenen-Charakter der europäischen Politik und das normative Potenzial der Legitimationsvermittlung zwischen Union und Bürgern durch die demokratisch verfassten Mitgliedstaaten. Die gegenwärtige Eurokrise allerdings zerstört die Fähigkeit demokratischer Mitgliedstaaten, die Ausübung europäischer Herrschaftsfunktionen zu legitimieren. Der Aufsatz erörtert die Implikationen dieser neuen Konstellation.1 Introduction 2 Legitimacy discourses The republican discourse The liberal discourse Differences 3 Constitutional democracies – and the European Union? 4 Legitimacy intermediation in the multilevel European polity 5 The end of legitimacy intermediation in the euro crisis Monetary Union and the failure of output legitimacy Rescuing the euro through supranational intervention 6 Legitimate supranational government? Input-oriented European legitimacy? 7 Reducing the burden on European legitimacy Reference