What makes or breaks a campaign to stop an invading plant pathogen?

Diseases in humans, animals and plants remain an important challenge in our society. Effective control of invasive pathogens often requires coordinated concerted action of a large group of stakeholders. Both epidemiological and human behavioural factors influence the outcome of a disease control campaign. In mathematical models that are frequently used to guide such campaigns, human behaviour is often ill-represented, if at all. Existing models of human, animal and plant disease that do incorporate participation or compliance are often driven by pay-offs or direct observations of the disease state. It is however very well known that opinion is an important driving factor of human decision making. Here we consider the case study of Citrus Huanglongbing disease (HLB), which is an acute bacterial disease that threatens the sustainability of citrus production across the world. We show how by coupling an epidemiological model of this invasive disease with an opinion dynamics model we are able to answer the question: What makes or breaks the effectiveness of a disease control campaign? Frequent contact between stakeholders and advisors is shown to increase the probability of successful control. More surprisingly, we show that informing stakeholders about the effectiveness of control methods is of much greater importance than prematurely increasing their perceptions of the risk of infection. We discuss the overarching consequences of this finding and the effect on human as well as plant disease epidemics

A demonstration of an affinity between pyrite and organic matter in a hydrothermal setting

One of the key-principles of the iron-sulphur world theory is to bring organic molecules close enough to interact with each other, using the surface of pyrite as a substrate in a hydrothermal setting. The present paper explores the relationship of pyrite and organic matter in a hydrothermal setting from the geological record; in hydrothermal calcite veins from Carboniferous limestones in central Ireland. Here, the organic matter is accumulated as coatings around, and through, pyrite grains. Most of the pyrite grains are euhedral-subhedral crystals, ranging in size from ca 0.1-0.5 mm in diameter, and they are scattered throughout the matrix of the vein calcite. The organic matter was deposited from a hydrothermal fluid at a temperature of at least 200°C, and gives a Raman signature of disordered carbon. This study points to an example from a hydrothermal setting in the geological record, demonstrating that pyrite can have a high potential for the concentration and accumulation of organic materials

Domain shuffling of a highly mutable ligand-binding fold drives adhesin generation across the bacterial kingdom

\ua9 2023 The Authors. Proteins: Structure, Function, and Bioinformatics published by Wiley Periodicals LLC. Bacterial fibrillar adhesins are specialized extracellular polypeptides that promote the attachment of bacteria to the surfaces of other cells or materials. Adhesin-mediated interactions are critical for the establishment and persistence of stable bacterial populations within diverse environmental niches and are important determinants of virulence. The fibronectin (Fn)-binding fibrillar adhesin CshA, and its paralogue CshB, play important roles in host colonization by the oral commensal and opportunistic pathogen Streptococcus gordonii. As paralogues are often catalysts for functional diversification, we have probed the early stages of structural and functional divergence in Csh proteins by determining the X-ray crystal structure of the CshB adhesive domain NR2 and characterizing its Fn-binding properties in vitro. Despite sharing a common fold, CshB_NR2 displays an ~1.7-fold reduction in Fn-binding affinity relative to CshA_NR2. This correlates with reduced electrostatic charge in the Fn-binding cleft. Complementary bioinformatic studies reveal that homologues of CshA/B_NR2 domains are widely distributed in both Gram-positive and Gram-negative bacteria, where they are found housed within functionally cryptic multi-domain polypeptides. Our findings are consistent with the classification of Csh adhesins and their relatives as members of the recently defined polymer adhesin domain (PAD) family of bacterial proteins

Glycosylation defects underlying fetal alcohol spectrum disorder: a novel pathogenetic model: “When the wine goes in, strange things come out” – S.T. Coleridge, The Piccolomini

Fetal alcohol spectrum disorder (FASD) is an umbrella term used to describe the craniofacial dysmorphic features, malformations, and disturbances in growth, neurodevelopment and behavior occurring in individuals prenatally exposed to alcohol. Fetal alcohol syndrome (FAS) represents the severe end of this spectrum. Many pathophysiological mechanisms have hitherto been proposed to account for the disrupted growth and morphogenesis seen in FAS. These include impaired cholesterol-modification of the Sonic hedgehog morphogen, retinoic acid deficiency, lipoperoxidative damage due to alcohol-induced reactive oxygen species combined with reduced antioxidant defences, and malfunctioning cell adhesion molecules. In this report, we propose a completely novel concept regarding the pathogenesis of FAS. Based on our observation that transferrin isoelectric focusing (TIEF) – the most widely used screening tool for congenital disorders of glycosylation (CDG) – was transiently abnormal in a newborn with FAS and a confirmed maternal history of gestational alcohol abuse, we came to believe that FAS exemplifies a congenital disorder of glycosylation secondary to alcohol-inflicted disruption of (N-linked) protein glycosylation. Various pieces of evidence were found in the literature to substantiate this hypothesis. This observation implies, among others, that one might need to consider the possibility of maternal alcohol consumption in newborns with transient glycosylation abnormalities. We also present an integrated pathophysiological model of FAS, which incorporates all existing theories mentioned above as well as our novel concept. This model highlights the pivotal role of disrupted isoprenoid metabolism in the origination of FAS

Reduction spheroids preserve a uranium isotope record of the ancient deep continental biosphere

S.M. acknowledges the support of the NASA Astrobiology Institute grant NNA13AA90A, Foundations of Complex Life, Evolution, Preservation and Detection on Earth and Beyond, and the European Union’s Horizon 2020 Research and Innovation Programme under Marie Skłodowska-Curie grant agreement 747877. Av.S.H. was supported by a NASA Astrobiology Institute Postdoctoral Fellowship and acknowledges the support of Xiangli Wang and Devon Cole for lab assistance. S.M. and Av.S.H. thank Noah Planavsky for technical advice, lab support, and comments on an early draft. J.P. was supported by NERC under grant number NE/L001764/1. The isotope facility at SUERC is supported by NERC. The authors thank the two anonymous referees for constructive criticisms that improved the manuscript.Peer reviewedPublisher PD

X-Ray Spectroscopy of Stars

(abridged) Non-degenerate stars of essentially all spectral classes are soft X-ray sources. Low-mass stars on the cooler part of the main sequence and their pre-main sequence predecessors define the dominant stellar population in the galaxy by number. Their X-ray spectra are reminiscent, in the broadest sense, of X-ray spectra from the solar corona. X-ray emission from cool stars is indeed ascribed to magnetically trapped hot gas analogous to the solar coronal plasma. Coronal structure, its thermal stratification and geometric extent can be interpreted based on various spectral diagnostics. New features have been identified in pre-main sequence stars; some of these may be related to accretion shocks on the stellar surface, fluorescence on circumstellar disks due to X-ray irradiation, or shock heating in stellar outflows. Massive, hot stars clearly dominate the interaction with the galactic interstellar medium: they are the main sources of ionizing radiation, mechanical energy and chemical enrichment in galaxies. High-energy emission permits to probe some of the most important processes at work in these stars, and put constraints on their most peculiar feature: the stellar wind. Here, we review recent advances in our understanding of cool and hot stars through the study of X-ray spectra, in particular high-resolution spectra now available from XMM-Newton and Chandra. We address issues related to coronal structure, flares, the composition of coronal plasma, X-ray production in accretion streams and outflows, X-rays from single OB-type stars, massive binaries, magnetic hot objects and evolved WR stars.Comment: accepted for Astron. Astrophys. Rev., 98 journal pages, 30 figures (partly multiple); some corrections made after proof stag

The football is medicine plaform-scientific evidence, large-scale implementation of evidence-based concepts and future perspectives

The idea that football can be used as therapy and as a high-intensity and literally breath-taking training regime goes back centuries. To take one prominent example, the French philosopher Voltaire describes in the Book of Fate (1747), how a patient is cured by playing with a sacred football: “… full-blown and carefully covered with the softest Leather. You must kick this Bladder, Sir, once a Day about your Hall for a whole Hour together, with all the Vigour and Activity you possibly can”, “Ogul, upon making the first Experiment, was ready to expire for want of Breath”, “In short, our Doctor in about 8 days Time, performed an absolute Cure. His Patient was as brisk, active and gay, as One in the Bloom of his Youth.”1 Today, Voltaire and his main character, philosopher Zadig, have been proved right: Football is indeed a breath-taking activity and it can be used as therapy. Albeit today's recommendations suggest a lower training frequency, longer training periods and encourage group-based training, and say that any football can be applied

Defining Feasibility and Pilot Studies in Preparation for Randomised Controlled Trials: Development of a Conceptual Framework

We describe a framework for defining pilot and feasibility studies focusing on studies conducted in preparation for a randomised controlled trial. To develop the framework, we undertook a Delphi survey; ran an open meeting at a trial methodology conference; conducted a review of definitions outside the health research context; consulted experts at an international consensus meeting; and reviewed 27 empirical pilot or feasibility studies. We initially adopted mutually exclusive definitions of pilot and feasibility studies. However, some Delphi survey respondents and the majority of open meeting attendees disagreed with the idea of mutually exclusive definitions. Their viewpoint was supported by definitions outside the health research context, the use of the terms ‘pilot’ and ‘feasibility’ in the literature, and participants at the international consensus meeting. In our framework, pilot studies are a subset of feasibility studies, rather than the two being mutually exclusive. A feasibility study asks whether something can be done, should we proceed with it, and if so, how. A pilot study asks the same questions but also has a specific design feature: in a pilot study a future study, or part of a future study, is conducted on a smaller scale. We suggest that to facilitate their identification, these studies should be clearly identified using the terms ‘feasibility’ or ‘pilot’ as appropriate. This should include feasibility studies that are largely qualitative; we found these difficult to identify in electronic searches because researchers rarely used the term ‘feasibility’ in the title or abstract of such studies. Investigators should also report appropriate objectives and methods related to feasibility; and give clear confirmation that their study is in preparation for a future randomised controlled trial designed to assess the effect of an intervention

Lack of Phylogeographic Structure in the Freshwater Cyanobacterium Microcystis aeruginosa Suggests Global Dispersal

Background : Free-living microorganisms have long been assumed to have ubiquitous distributions with little biogeographic signature because they typically exhibit high dispersal potential and large population sizes. However, molecular data provide contrasting results and it is far from clear to what extent dispersal limitation determines geographic structuring of microbial populations. We aimed to determine biogeographical patterns of the bloom-forming freshwater cyanobacterium Microcystis aeruginosa. Being widely distributed on a global scale but patchily on a regional scale, this prokaryote is an ideal model organism to study microbial dispersal and biogeography. Methodology/Principal Findings : The phylogeography of M. aeruginosa was studied based on a dataset of 311 rDNA internal transcribed spacer (ITS) sequences sampled from six continents. Richness of ITS sequences was high (239 ITS types were detected). Genetic divergence among ITS types averaged 4% (maximum pairwise divergence was 13%). Preliminary analyses revealed nearly completely unresolved phylogenetic relationships and a lack of genetic structure among all sequences due to extensive homoplasy at multiple hypervariable sites. After correcting for this, still no clear phylogeographic structure was detected, and no pattern of isolation by distance was found on a global scale. Concomitantly, genetic differentiation among continents was marginal, whereas variation within continents was high and was mostly shared with all other continents. Similarly, no genetic structure across climate zones was detected. Conclusions/Significance : The high overall diversity and wide global distribution of common ITS types in combination with the lack of phylogeographic structure suggest that intercontinental dispersal of M. aeruginosa ITS types is not rare, and that this species might have a truly cosmopolitan distribution