8,137 research outputs found

    Eukaryotic parasites are integral to a productive microbial food web in oxygen-depleted waters

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    © The Author(s), 2022]. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Suter, E. A., Pachiadaki, M., Taylor, G. T., & Edgcomb, V. P. Eukaryotic parasites are integral to a productive microbial food web in oxygen-depleted waters. Frontiers in Microbiology, 12, (2022): 764605, https://doi.org/10.3389/fmicb.2021.764605.Oxygen-depleted water columns (ODWCs) host a diverse community of eukaryotic protists that change dramatically in composition over the oxic-anoxic gradient. In the permanently anoxic Cariaco Basin, peaks in eukaryotic diversity occurred in layers where dark microbial activity (chemoautotrophy and heterotrophy) were highest, suggesting a link between prokaryotic activity and trophic associations with protists. Using 18S rRNA gene sequencing, parasites and especially the obligate parasitic clade, Syndiniales, appear to be particularly abundant, suggesting parasitism is an important, but overlooked interaction in ODWC food webs. Syndiniales were also associated with certain prokaryotic groups that are often found in ODWCs, including Marinimicrobia and Marine Group II archaea, evocative of feedbacks between parasitic infection events, release of organic matter, and prokaryotic assimilative activity. In a network analysis that included all three domains of life, bacterial and archaeal taxa were putative bottleneck and hub species, while a large proportion of edges were connected to eukaryotic nodes. Inclusion of parasites resulted in a more complex network with longer path lengths between members. Together, these results suggest that protists, and especially protistan parasites, play an important role in maintaining microbial food web complexity, particularly in ODWCs, where protist diversity and microbial productivity are high, but energy resources are limited relative to euphotic waters.This work was supported by the National Science Foundation (NSF) grants (OCE-1336082 to VE and OCE-1335436 and OCE-1259110 to GT). The Cyverse infrastructure and resources are supported by the NSF under Award Numbers DBI-0735191, DBI-1265383, and DBI-1743442 (www.cyverse.org). Support was also provided by the Faculty Scholarship and Academic Advancement Committee at Molloy College

    In search of phylogenetic congruence between molecular and morphological data in bryozoans with extreme adult skeletal heteromorphy

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    peerreview_statement: The publishing and review policy for this title is described in its Aims & Scope. aims_and_scope_url: http://www.tandfonline.com/action/journalInformation?show=aimsScope&journalCode=tsab20© Crown Copyright 2015. This document is the author's final accepted/submitted version of the journal article. You are advised to consult the publisher's version if you wish to cite from it

    Solving Tree Problems with Category Theory

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    Artificial Intelligence (AI) has long pursued models, theories, and techniques to imbue machines with human-like general intelligence. Yet even the currently predominant data-driven approaches in AI seem to be lacking humans' unique ability to solve wide ranges of problems. This situation begs the question of the existence of principles that underlie general problem-solving capabilities. We approach this question through the mathematical formulation of analogies across different problems and solutions. We focus in particular on problems that could be represented as tree-like structures. Most importantly, we adopt a category-theoretic approach in formalising tree problems as categories, and in proving the existence of equivalences across apparently unrelated problem domains. We prove the existence of a functor between the category of tree problems and the category of solutions. We also provide a weaker version of the functor by quantifying equivalences of problem categories using a metric on tree problems.Comment: 10 pages, 4 figures, International Conference on Artificial General Intelligence (AGI) 201

    Manipulation of FASTQ data with Galaxy

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    Summary: Here, we describe a tool suite that functions on all of the commonly known FASTQ format variants and provides a pipeline for manipulating next generation sequencing data taken from a sequencing machine all the way through the quality filtering steps

    Probiotic Supplementation and Gastrointestinal Endotoxemia Before and After the Marathon Des Sables.

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    Whilst evidence of increased gastrointestinal endotoxemia (GE) has been previously demonstrated during single-day ultra-endurance events, less is known on the prevalence of GE following extreme ultra-events such as the Marathon Des Sables (MDS). The potential benefit of probiotic formulas on gut integrity during ultra-endurance events also requires further investigation. PURPOSE: To assess the impact of probiotic supplementation with or without glutamine on GE prevalence in runners competing in a multi-day ultra-run (MDS). METHODS: Thirty four healthy participants from the 2015 MDS UK cohort volunteered for a 12 week pre-race intervention and were randomly assigned to either: probiotic (PRO; 100mg.d-1 lactobacillus acidophilus) (age 40 ±3 yrs., weight 79.4 ±2.0kg, VO2max 4.2 ±0.1 L.min-1), probiotic with glutamine (PROglut; 40.5mg.d-1 lactobacillus acidophilus and 900mg.d-1L-glutamine) (age 39 ±2 yrs., weight 70.6 ±4.8 kg, VO2max 4.0 ±0.2 L.min-1) and control (CON) (age 42±3 yrs., weight 79.2 ±3.8 kg, VO2max 4.0 ±0.3 L.min-1). Plasma lipopolysaccharides (LPS) (via Limulus Amebocyte Lysate chromogenic endotoxin quantification) were assessed at weeks 0, 12, post-race and 7 days post-race. Performance data was collated from official timing chips. Data presented as mean ±SE. RESULTS: Mild to moderate GE was prevalent in all groups at baseline (PRO 9.71 ±0.85pg.ml-1, PROglut 9.89 ±1.43 pg.ml-1, CON 9.40 ±0.57 pg.ml-1; P>0.05). Whilst LPS, post intervention, was lower in PROglut there was no significance between groups (9.81 ±1.47pg.ml-1 vs 12.80 ±0.93pg.ml-1 (PRO) vs 11.72 ±1.08 pg.mol-1 (CON); P>0.05). LPS were evidently reduced 6hrs post-race, but not different between groups (PRO: 7.29 ±1.41 pg.ml-1, PROglut: 6.95 ±0.94 pg.ml-1, CON: 9.73 ±1.39 pg.ml-1; P>0.05).Plasma LPS returned to baseline levels 7 days post-race (PRO 7.60 ±0.95 pg.ml-1, PROglut 10.41 ±1.04 pg.ml-1, CON 8.57 ±0.75 pg.ml-1; P>0.05). Race performance (hrs:mins) was not significant between groups, despite PRO and PROglut being ~9hrs faster than CON (41:28±2:31 vs 41:58±4:02 vs 50:43±4:38; P>0.05). CONCLUSION: Moderate GE was prevalent in all groups pre-race and fell significantly during the short-term recovery period. Despite promising results neither probiotic formula had a significant impact on GE or race performance

    Stage-Specific Sampling by Pattern Recognition Receptors during Candida albicans Phagocytosis

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    Candida albicans is a medically important pathogen, and recognition by innate immune cells is critical for its clearance. Although a number of pattern recognition receptors have been shown to be involved in recognition and phagocytosis of this fungus, the relative role of these receptors has not been formally examined. In this paper, we have investigated the contribution of the mannose receptor, Dectin-1, and complement receptor 3; and we have demonstrated that Dectin-1 is the main non-opsonic receptor involved in fungal uptake. However, both Dectin-1 and complement receptor 3 were found to accumulate at the site of uptake, while mannose receptor accumulated on C. albicans phagosomes at later stages. These results suggest a potential role for MR in phagosome sampling; and, accordingly, MR deficiency led to a reduction in TNF-α and MCP-1 production in response to C. albicans uptake. Our data suggest that pattern recognition receptors sample the fungal phagosome in a sequential fashion

    The evolution of the specific star formation rate of massive galaxies to z ~ 1.8 in the E-CDFS

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    We study the evolution of the star formation rate (SFR) of mid-infrared (IR) selected galaxies in the extended Chandra Deep Field South (E-CDFS). We use a combination of U-K GaBoDS and MUSYC data, deep IRAC observations from SIMPLE, and deep MIPS data from FIDEL. This unique multi-wavelength data set allows us to investigate the SFR history of massive galaxies out to redshift z ~ 1.8. We determine star formation rates using both the rest-frame ultraviolet luminosity from young, hot stars and the total IR luminosity of obscured star formation obtained from the MIPS 24 um flux. We find that at all redshifts the galaxies with higher masses have substantially lower specific star formation rates than lower mass galaxies. The average specific star formation rates increase with redshift, and the rate of incline is similar for all galaxies (roughly (1+z)^{n}, n = 5.0 +/- 0.4). It does not seem to be a strong function of galaxy mass. Using a subsample of galaxies with masses M_*> 10^11 M_sun, we measured the fraction of galaxies whose star formation is quenched. We consider a galaxy to be in quiescent mode when its specific star formation rate does not exceed 1/(3 x t_H), where t_H is the Hubble time. The fraction of quiescent galaxies defined as such decreases with redshift out to z ~ 1.8. We find that, at that redshift, 19 +/-9 % of the M_* > 10^11 M_sun sources would be considered quiescent according to our criterion.Comment: 7 pages, 6 figures, accepted for publication in Ap

    Efficacy of the enteroadsorbent Silicol®gel in adults with irritable bowel syndrome subtypes IBS-D or mixed : observational open-label study

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    Background. Irritable bowel syndrome (IBS) is a common chronic gut-brain interaction disorder with limited effective treatment options. Intestinal adsorbents have a high adsorption capacity for gut irritants and may provide nonpharmacological alternatives. Objectives. This post marketing study is aimed at providing up-to-date evidence to support the safety and efficacy in normal use of an established medical device for IBS treatment. Methods. In this open-label, observational study, adults with IBS with predominant diarrhoea (IBS-D) or IBS with mixed bowel habits (IBS-M), according to Rome IV criteria, received 4 weeks of treatment with the enteroadsorbent Silicol®gel, a CE-certified, licenced, medical device containing colloidal silicic acid. Eligible participants were assessed at baseline (visit 1; in-clinic) and after 1 (visit 2; telephone), 2 (visit 3; telephone), and 4 (visit 4; in-clinic) weeks of treatment. The primary endpoint was the proportion of participants with an overall reduction in the IBS severity scoring system IBS SSS>50, representing clinically meaningful improvement. Key secondary endpoints were a reduction in common IBS symptoms and improved quality of life (QoL). Results. Among the 67 treated participants (IBS-D: 37; IBS-M: 30), 65 completed the study. At visit 4, 83.6% (56/67) of participants achieved a reduction in IBS SSS>50. The mean (standard deviation [SD]) IBS SSS was 323.4 (55.7) at visit 1 and 160.3 (90.3) at visit 4 (overall change: -163.1 (101.7); 95% confidence interval [CI] 138.3, 187.9, p<0.001). Compared with visit 1, significant reductions in the severity of all key IBS symptoms and overall improvement in QoL were observed at visit 4 (p<0.001), with improvements observed from visits 1 and 2. Conclusions. In this open-label study of participants with IBS-D and IBS-M, Silicol®gel provided clinically significant improvement in IBS symptoms, demonstrating that enteroadsorbents may be clinically beneficial in this population

    Enhanced visualisation of fast frequency phenomena as exhibited in the Gb transmission system

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    © 2019 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.© 2019 IEEE. This paper investigates fast frequency phenomena as exhibited in the Great Britain (GB) transmission system as a consequence of the relationship of system disturbances to the changing inertia of the system. Fast frequency phenomena are studied with specific reference to real case studies associated with GB transmission system disturbances as recorded by Phasor Measurement Units located across the transmission system. The intrinsic behavior of the phenomena is investigated, observed and analyzed using enhanced 2D and 3D visualization tools. The novel visualization tools and techniques have been developed using Matlab and the impact area of system disturbances with regard to Rate of Change of Frequency and Vector Shift can also be observed and analyzed via the developed visualization tool.National Grid Electricity System Operator; Office of Gas and Electricity Markets (OFGEM
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