2,153 research outputs found

    “Equator Crossing” of Shatsky Rise?: New insights on Shatsky Rise tectonic motion from the downhole magnetic architecture of the uppermost lava sequences at Tamu Massif

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    Author Posting. © American Geophysical Union, 2012. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geophysical Research Letters 39 (2012): L21301, doi:10.1029/2012GL052967.Shatsky Rise is a Large Igneous Province (LIP) currently located in the northwestern Pacific. New downhole magnetic logging data from Integrated Ocean Drilling Program (IODP) Hole U1347A at Tamu Massif of Shatsky Rise captured the magnetic architecture in the uppermost lava sequence, providing a rare opportunity to investigate a time series of the intra-plate volcanism in conjunction with the Pacific plate construction history centered at the triple junction. Logging data results indicate that Tamu Massif was formed during normal polarity periods south of the paleoequator and crossed the equator at some point in the M19–M17 period. Combining these new observations with previous interpretations of the massif's tectonic history, a time series of the latitudinal tectonic motion of a LIP and the underlying Pacific plate during the plateau formation is postulated.This project was supported by the IODP-US Science Support Program (Consortium for Ocean Leadership) Expedition 324 Post Expedition Award.2013-05-0

    Lipid coated liquid crystal droplets for the on-chip detection of antimicrobial peptides

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    We describe a novel biosensor based on phospholipid-coated nematic liquid crystal (LC) droplets and demonstrate the detection of Smp43, a model antimicrobial peptide (AMP) from the venom of North African scorpion Scorpio maurus palmatus. Mono-disperse lipid-coated LC droplets of diameter 16.7 ± 0.2 μm were generated using PDMS microfluidic devices with a flow-focusing configuration and were the target for AMPs. The droplets were trapped in a bespoke microfluidic trap structure and were simultaneously treated with Smp43 at gradient concentrations in six different chambers. The disruption of the lipid monolayer by the Smp43 was detected (<6 μM) at concentrations well within its biologically active range, indicated by a dramatic change in the appearance of the droplets associated with the transition from a typical radial configuration to a bipolar configuration, which is readily observed by polarizing microscopy. This suggests the system has feasibility as a drug-discovery screening tool. Further, compared to previously reported LC droplet biosensors, this LC droplet biosensor with a lipid coating is more biologically relevant and its ease of use in detecting membrane-related biological processes and interactions has the potential for development as a reliable, low-cost and disposable point of care diagnostic tool

    Once a feminist: Lynne Segal on Grace Paley’s The Little Disturbances of Man

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    The following contributions came in response to a request, sent to a number of key figures in feminism today, to write on a text that had been formative for their thinking as feminists. The chosen text could be a theory, a novel, an artwork, a performance, a poem: one that had stimulated, or even revolutionised, their ideas. As we hoped, this project has created a selection of texts central to our many and different experiences as feminists. I used to say that Margaret Drabble's The Garrick Year was the story of my life, in my early twenties, as if I was just a creature of time and circumstance. I read The Garrick Year sometime between October 1965, when my first child was born, and the end of 1967, before my marriage disintegrated. Like the heroine Emma Evans, I married a successful actor, had a child, and followed his career—which in the novel led Emma to Hereford for a summer season of plays

    The c2d Spitzer Spectroscopic Survey Of Ices Around Low-Mass Young Stellar Objects. I. H2O And The 5-8 Mu M Bands

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    To study the physical and chemical evolution of ices in solar-mass systems, a spectral survey is conducted of a sample of 41 low-luminosity YSOs (L similar to 0.1-10 L-circle dot) using 3-38 mu m Spitzer and ground-based spectra. The sample is complemented with previously published Spitzer spectra of background stars and with ISO spectra of well-studied massive YSOs (L similar to 10(5) L-circle dot). The long-known 6.0 and 6.85 mu m bands are detected toward all sources, with the Class 0-type YSOs showing the deepest bands ever observed. The 6.0 mu m band is often deeper than expected from the bending mode of pure solid H2O. The additional 5-7 mu m absorption consists of five independent components, which, by comparison to laboratory studies, must be from at least eight different carriers. Much of this absorption is due to simple species likely formed by grain surface chemistry, at abundances of 1%-30% for CH3OH, 3%-8% for NH3, 1%-5% for HCOOH, similar to 6% for H2CO, and similar to 0.3% for HCOO- relative to solid H2O. The 6.85 mu m band has one or two carriers, of which one may be less volatile than H2O. Its carrier(s) formed early in the molecular cloud evolution and do not survive in the diffuse ISM. If an NH4+- containing salt is the carrier, its abundance relative to solid H2O is similar to 7%, demonstrating the efficiency of low-temperature acid-base chemistry or cosmic-ray-induced reactions. Possible origins are discussed for enigmatic, very broad absorption between 5 and 8 mu m. Finally, the same ices are observed toward massive and low-mass YSOs, indicating that processing by internal UV radiation fields is a minor factor in their early chemical evolution.NWO SpinozaNOVAEuropean Research Training Network PLANETS HPRN-CT-2002-00308NASA Origins NAG5-13050NASA Hubble Fellowship 01201.01NASA NAS 5-26555Astronom

    The harlequin ladybird, Harmonia axyridis: global perspectives on invasion history and ecology

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    The harlequin ladybird, Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae), is native to Asia but has been intentionally introduced to many countries as a biological control agent of pest insects. In numerous countries, however, it has been introduced unintentionally. The dramatic spread of H. axyridis within many countries has been met with considerable trepidation. It is a generalist top predator, able to thrive in many habitats and across wide climatic conditions. It poses a threat to biodiversity, particularly aphidophagous insects, through competition and predation, and in many countries adverse effects have been reported on other species, particularly coccinellids. However, the patterns are not consistent around the world and seem to be affected by many factors including landscape and climate. Research on H. axyridis has provided detailed insights into invasion biology from broad patterns and processes to approaches in surveillance and monitoring. An impressive number of studies on this alien species have provided mechanistic evidence alongside models explaining large-scale patterns and processes. The involvement of citizens in monitoring this species in a number of countries around the world is inspiring and has provided data on scales that would be otherwise unachievable. Harmonia axyridis has successfully been used as a model invasive alien species and has been the inspiration for global collaborations at various scales. There is considerable scope to expand the research and associated collaborations, particularly to increase the breadth of parallel studies conducted in the native and invaded regions. Indeed a qualitative comparison of biological traits across the native and invaded range suggests that there are differences which ultimately could influence the population dynamics of this invader. Here we provide an overview of the invasion history and ecology of H. axyridis globally with consideration of future research perspectives. We reflect broadly on the contributions of such research to our understanding of invasion biology while also informing policy and people.&nbsp; Additional co-authors: Artur Gil, Audrey A. Grez, Thomas Guillemaud, Danny Haelewaters, Annette Herz, Alois Honek, Andy G. Howe, Cang Hui, William D. Hutchison, Marc Kenis, Robert L. Koch, Jan Kulfan, Lori Lawson Handley, Eric Lombaert, Antoon Loomans, John Losey, Alexander O. Lukashuk, Dirk Maes, Alexandra Magro, Gilles San Martin, Zdenka Martinkova, Ingrid A. Minnaar, Oldřich Nedved, Marina J. Orlova-Bienkowskaja, Naoya Osawa, Wolfgang Rabitsch, Hans Peter Ravn, Gabriele Rondoni, Steph L. Rorke, Sergey K. Ryndevich, May-Guri Saethre, John J. Sloggett, Antonio Onofre Soares, Riaan Stals, Axel Vandereycken, Paul van Wielink, Sandra Vigl&aacute;&scaron;ov&aacute;, Peter Zach, Ilya A. Zakharov, Tania Zaviezo, Zihua Zha

    Unlocking the health system barriers to maximise the uptake and utilisation of molecular diagnostics in low- and middle- income country setting

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    The study was funded by the European and Developing Countries Clinical Trials Partnership (EDCTP), grant TWENDE-EDCTP-CSA-2014-283.Background : Early access to diagnosis is crucial for effective management of any disease including tuberculosis (TB). We investigated the barriers and opportunities to maximise uptake and utilisation of molecular diagnostics in routine healthcare settings. Methods : Using the implementation of World Health Organisation approved TB diagnostics, Xpert MTB/RIF and Line Probe Assay (LPA) as a benchmark we evaluated the barriers and how they could be unlocked to maximise uptake and utilisation of molecular diagnostics. Results : Health officers representing 190 districts/counties participated in the survey across Kenya, Tanzania and Uganda. The survey findings were corroborated by 145 healthcare facility (HCF) audits and 11 policymaker engagement workshops. Xpert MTB/RIF coverage was 66%, falling behind microscopy and clinical diagnosis by 33% and 1% respectively. Stratified by HCF type, Xpert MTB/RIF implementation was 56%, 96% and 95% at district-, regional- and national referral- hospital levels. LPA coverage was 4%, 3% below culture across the three countries. Out of 111 HCFs with Xpert MTB/RIF, 37 (33%) utilised it to full capacity, performing ≥8 tests per day of which 51% of these were level five (zonal consultant and national referral) HCFs. Likewise, 75% of LPA was available at level five HCFs. Underutilisation of Xpert MTB/RIF and LPA was mainly attributed to inadequate- utilities, 26% and human resource, 22%. Underfinancing was the main reason underlying failure to acquire molecular diagnostics. Second to underfinancing was lack of awareness with 33% healthcare administrators and 49% practitioners were unaware of LPA as TB diagnostic. Creation of a health tax and decentralising its management was proposed by policymakers as a booster of domestic financing needed to increase access to diagnostics. Conclusion : Our findings suggest higher uptake and utilisation of molecular diagnostics at tertiary level HCFs contrary to the WHO recommendation. Country-led solutions are crucial for unlocking barriers to increase access to diagnostics.Publisher PDFPeer reviewe
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