75 research outputs found

    The genome of the sea urchin Strongylocentrotus purpuratus

    Get PDF
    We report the sequence and analysis of the 814-megabase genome of the sea urchin Strongylocentrotus purpuratus, a model for developmental and systems biology. The sequencing strategy combined whole-genome shotgun and bacterial artificial chromosome (BAC) sequences. This use of BAC clones, aided by a pooling strategy, overcame difficulties associated with high heterozygosity of the genome. The genome encodes about 23,300 genes, including many previously thought to be vertebrate innovations or known only outside the deuterostomes. This echinoderm genome provides an evolutionary outgroup for the chordates and yields insights into the evolution of deuterostomes

    ‘ASMR’ Autobiographies and the (Life-)Writing of Digital Subjectivity

    Get PDF
    For years now, a growing online subculture has been exchanging videos designed to induce ‘autonomous sensory meridian response’ (ASMR), a mysterious, blissfully relaxing tingling sensation held to alleviate anxiety, pain, insomnia and depression. Emerging from online health forums, ASMR culture today centres on YouTube, where ‘ASMRtists’ have used the feedback mechanisms built into social media platforms to refine a repertoire of ‘trigger’ techniques. Exemplifying a wider trend for using ‘ambient media’ as mood modulators and task facilitators (Roquet, 2016), ASMR culture’s use of the word ‘trigger’ is telling, gesturing towards what Halberstam (2014) sees as a shift away from the Freudian notion of ‘memory as a palimpsest’ towards one of memory as ‘a live wire sitting in the psyche waiting for a spark’, whereby digital subjects become black-boxed nodes in a cybernetic circuit. This shift has serious implications for the humanities and is particularly resonant for scholars of life-writing. As McNeill (2012) argues, digital technologies ‘complicate[] definitions of the self and its boundaries, both dismantling and sustaining the humanist subject in practices of personal narrative’ (p. 65). The resulting friction is highlighted in ‘ASMR autobiographies’: texts narrating the author’s experiences of ASMR and their discovery of online ASMR communities. Echoing familiar auto/biographical forms, from medical case histories and coming out narratives to tales of religious conversion, these texts show that the models of subjectivity we have inherited from Enlightenment philosophy, religion, psychology and Romantic literature retain some cultural purchase. But they also suggest digital media are fostering new understandings of personhood informed by cybernetics, evolutionary psychology, behaviourism and neuroscience. Focusing on works by Andrew MacMuiris, Andrea Seigel and Jon Kersey while also addressing a range of other texts, this article asks what ASMR autobiographies can tell us about digital subjectivity

    The Effect of Iron Limitation on the Transcriptome and Proteome of Pseudomonas fluorescens Pf-5

    Get PDF
    One of the most important micronutrients for bacterial growth is iron, whose bioavailability in soil is limited. Consequently, rhizospheric bacteria such as Pseudomonas fluorescens employ a range of mechanisms to acquire or compete for iron. We investigated the transcriptomic and proteomic effects of iron limitation on P. fluorescens Pf-5 by employing microarray and iTRAQ techniques, respectively. Analysis of this data revealed that genes encoding functions related to iron homeostasis, including pyoverdine and enantio-pyochelin biosynthesis, a number of TonB-dependent receptor systems, as well as some inner-membrane transporters, were significantly up-regulated in response to iron limitation. Transcription of a ribosomal protein L36-encoding gene was also highly up-regulated during iron limitation. Certain genes or proteins involved in biosynthesis of secondary metabolites such as 2,4-diacetylphloroglucinol (DAPG), orfamide A and pyrrolnitrin, as well as a chitinase, were over-expressed under iron-limited conditions. In contrast, we observed that expression of genes involved in hydrogen cyanide production and flagellar biosynthesis were down-regulated in an iron-depleted culture medium. Phenotypic tests revealed that Pf-5 had reduced swarming motility on semi-solid agar in response to iron limitation. Comparison of the transcriptomic data with the proteomic data suggested that iron acquisition is regulated at both the transcriptional and post-transcriptional levels

    Exposure assessment of process-related contaminants in food by biomarker monitoring

    Get PDF
    Exposure assessment is a fundamental part of the risk assessment paradigm, but can often present a number of challenges and uncertainties. This is especially the case for process contaminants formed during the processing, e.g. heating of food, since they are in part highly reactive and/or volatile, thus making exposure assessment by analysing contents in food unreliable. New approaches are therefore required to accurately assess consumer exposure and thus better inform the risk assessment. Such novel approaches may include the use of biomarkers, physiologically based kinetic (PBK) modelling-facilitated reverse dosimetry, and/or duplicate diet studies. This review focuses on the state of the art with respect to the use of biomarkers of exposure for the process contaminants acrylamide, 3-MCPD esters, glycidyl esters, furan and acrolein. From the overview presented, it becomes clear that the field of assessing human exposure to process-related contaminants in food by biomarker monitoring is promising and strongly developing. The current state of the art as well as the existing data gaps and challenges for the future were defined. They include (1) using PBK modelling and duplicate diet studies to establish, preferably in humans, correlations between external exposure and biomarkers; (2) elucidation of the possible endogenous formation of the process-related contaminants and the resulting biomarker levels; (3) the influence of inter-individual variations and how to include that in the biomarker-based exposure predictions; (4) the correction for confounding factors; (5) the value of the different biomarkers in relation to exposure scenario’s and risk assessment, and (6) the possibilities of novel methodologies. In spite of these challenges it can be concluded that biomarker-based exposure assessment provides a unique opportunity to more accurately assess consumer exposure to process-related contaminants in food and thus to better inform risk assessment

    Social Relationships and Mortality Risk: A Meta-analytic Review

    Get PDF
    In a meta-analysis, Julianne Holt-Lunstad and colleagues find that individuals' social relationships have as much influence on mortality risk as other well-established risk factors for mortality, such as smoking
    corecore