7,112 research outputs found

    Effects of Paecilomyces lilacinus protease and chitinase on the eggshell structures and hatching of Meloidogyne javanica juveniles

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    A serine protease and an enzyme preparation consisting of six chitinases, previously semi-purified from a liquid culture of Paecilomyces lilacinus strain 251, were applied to Meloidogyne javanica eggs to study the effect of the enzymes on eggshell structures. Transmission electron microscopic studies revealed that the protease and chitinases drastically altered the eggshell structures when applied individually or in combination. In the protease-treated eggs, the lipid layer disappeared and the chitin layer was thinner than in the control. The eggs treated with chitinases displayed large vacuoles in the chitin layer, and the vitelline layer was split and had lost its integrity. The major changes in the eggshell structures occurred by the combined effect of P. lilacinus protease and chitinases. The lipid layer was destroyed; the chitin layer hydrolyzed and the vitelline layer had lost integrity. The effect of P. lilacinus protease and chitinase enzymes on the hatching of M. javanica juveniles was also compared with a commercially available bacterial chitinase. The P. lilacinus protease and chitinase enzymes, either individually or in combination, reduced hatching of M. javanica juveniles whereas a commercial bacterial chitinase had an enhancing effect. Some juveniles hatched when the eggs were exposed to a fungal protease and chitinase mixture. We also established that P. lilacinus chitinases retained their activity in the presence of endogenous protease activity. © 2004 Elsevier Inc. All rights reserved

    School-university partnerships: Lessons learned from 10 years of spectroscopy for teachers and post 16 students

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    Spectroscopy covers a wide range of analytical techniques, a small sub-set of which UK pre-university chemistry students are required to study. The expense of such equipment means that it is not available to the vast majority of schools whilst it is commonplace in university chemistry departments. This article discusses the evolution of the Bristol ChemLabS spectroscopy outreach activities. The advantages and disadvantages of this method of engagement for both the participants and the providers are discussed from 10 years of activity

    Generation of Internal Waves by Eddies Impinging on the Western Boundary of the North Atlantic

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    This is the final version. Available from the American Meteorological Society via the DOI in this recordDespite the major role played by mesoscale eddies in redistributing the energy of the large-scale circulation, our understanding of their dissipation is still incomplete. This study investigates the generation of internal waves by decaying eddies in the North Atlantic western boundary. The eddy presence and decay are measured from the altimetric surface relative vorticity associated with an array of full-depth current meters extending ~100 km offshore at 26.5°N. In addition, internal waves are analyzed over a topographic rise from 2-yr high-frequency measurements of an acoustic Doppler current profiler (ADCP), which is located 13 km offshore in 600-m deep water. Despite an apparent polarity independence of the eddy decay observed from altimetric data, the flow in the deepest 100 m is enhanced for anticyclones (25.2 cm s−1) compared with cyclones (−4.7 cm s−1). Accordingly, the internal wave field is sensitive to this polarity-dependent deep velocity. This is apparent from the eddy-modulated enhanced dissipation rate, which is obtained from a finescale parameterization and exceeds 10−9 W kg−1 for near-bottom flows greater than 8 cm s−1. The present study underlines the importance of oceanic western boundaries for removing the energy of low-mode westward-propagating eddies to higher-mode internal waves.The RAPID-WATCH MOC monitoring project is funded by the U.K. Natural Environment Research Council, the U.S. National Science Foundation, and the U.S. National Oceanic and Atmospheric Administration. L. Clément was supported by NERC Grant NE/I528626/1. The participation of K. L. Sheen and J. A. Brearley in this study was supported by NERC Grants NE/E007058/1 and NE/E005667/1. A.C.N.G. acknowledges the support of a Philip Leverhulme Prize

    What is the nature and extent of evidence on methodologies for monitoring and evaluating marine spatial management measures in UK and similar coastal waters? A systematic map protocol

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    Background Anthropogenic degradation of marine ecosystems is widely accepted as a major social-ecological problem. The growing urgency to better manage marine ecosystems has led to the increasing application of ‘spatial management measures’ including marine protected areas, sectoral (e.g. fishery) closures, and marine spatial planning. However, the designation of varied spatial management regimes is just the first step; achievement of objectives relies upon effective implementation, monitoring, evaluation and adaptation. Despite spatial management being a core component of the marine management portfolio, to our knowledge, there is no systematic overview of the evidence on methodologies available, and employed, to monitor and evaluate their effectiveness across social, economic and ecological outcomes. Methods This systematic map will examine existing evidence describing methodologies for monitoring the effects, and evaluating the effectiveness, of marine spatial management across ecological, social and economic outcomes. Our aim is to provide a resource for decision-makers, primarily in the UK but also internationally, that supports effective marine management, and to describe the current evidence base. Identification and evaluation of relevant studies will therefore be restricted to coastal countries identified by our Stakeholder Group as being relevant to the UK, and searches will be restricted to the period 2009 to 2019 to align with the current UK policy context. Searches for relevant grey and academic literature, published in English, will be conducted in four bibliographic search engines, Google Scholar, 38 organisational websites and one specialist data repository. Eligibility screening will be conducted first at title and abstract level, and then at full text. Coding and meta-data extraction from eligible studies will include: bibliographic information, general information about the spatial management measure studied, and methodological information on the monitoring and evaluation undertaken. Consistency checking amongst reviewers will be undertaken during screening, coding and data extraction phases. The outcome of the systematic map will be a database that displays the meta-data of identified relevant studies. Findings will be presented in a descriptive report detailing the evaluation approaches and analytical methodologies employed, and data collection methods applied and/or data required by relevant studies to inform evaluations on the effectiveness of marine spatial management measures

    The many positive impacts of participating in outreach activities on postgraduate students

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    Postgraduate students are excellent role models for school students, where their passion and energy play a vital role in engaging younger students and spreading enthusiasm and excitement about science. However, participating in outreach is not a one way activity for these postgraduate students. Through focus groups we show that the postgraduate students perceive that there are many benefits for themselves. These benefits are identified and discussed. This paper also contrasts the postgraduate with their undergraduate counterpart in terms of their contributions to engagement activities

    A viral CTL escape mutation leading to immunoglobulin-like transcript 4-mediated functional inhibition of myelomonocytic cells

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    Viral mutational escape can reduce or abrogate recognition by the T cell receptor (TCR) of virus-specific CD8+ T cells. However, very little is known about the impact of cytotoxic T lymphocyte (CTL) epitope mutations on interactions between peptide–major histocompatibility complex (MHC) class I complexes and MHC class I receptors expressed on other cell types. Here, we analyzed a variant of the immunodominant human leukocyte antigen (HLA)-B2705–restricted HIV-1 Gag KK10 epitope (KRWIILGLNK) with an L to M amino acid substitution at position 6 (L6M), which arises as a CTL escape variant after primary infection but is sufficiently immunogenic to elicit a secondary, de novo HIV-1–specific CD8+ T cell response with an alternative TCR repertoire in chronic infection. In addition to altering recognition by HIV-1–specific CD8+ T cells, the HLA-B2705–KK10 L6M complex also exhibits substantially increased binding to the immunoglobulin-like transcript (ILT) receptor 4, an inhibitory MHC class I–specific receptor expressed on myelomonocytic cells. Binding of the B2705–KK10 L6M complex to ILT4 leads to a tolerogenic phenotype of myelomonocytic cells with lower surface expression of dendritic cell (DC) maturation markers and co-stimulatory molecules. These data suggest a link between CTL-driven mutational escape, altered recognition by innate MHC class I receptors on myelomonocytic cells, and functional impairment of DCs, and thus provide important new insight into biological consequences of viral sequence diversificatio

    Cognitive and sensorimotor function in participants being treated for trigeminal neuralgia pain

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    Background Trigeminal neuralgia (TN) is an orofacial condition defined by reoccurring, spontaneous, short-lived but excruciating stabbing pain. Pharmacological interventions constitute the first-line treatment for TN, with antiepileptic drugs commonly prescribed. People treated for TN pain with antiepileptic drugs describe cognitive and motor difficulties affecting activities of daily living, and report poorer quality of life. We undertook the first comprehensive objective evaluation of sensorimotor and cognitive performance in participants being treated for TN pain with antiepileptic drugs relative to age-matched controls. Methods Participants (43 TN, 41 control) completed a battery of sensorimotor (steering, aiming and tracking) and cognitive (working memory, processing speed, inhibition) tasks. Results The TN group performed significantly worse than controls on the sensorimotor tracking and aiming tasks and across all cognitive measures. Conclusions The data explain why patients treated with antiepileptic drugs report impairment when conducting activities of daily living (given the need for cognitive and motor capability within most of these). The study is an important first step in: (i) ensuring there is adequate information on the impact of pharmacological treatment; (ii) identifying measures to determine optimal medication dosage and track change over time; (iii) creating an evidence base that could allow scientific justification of alternative pain treatment options for TN (e.g. the costs/benefits of surgery)

    Cognitive and sensorimotor function in participants being treated for trigeminal neuralgia pain

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    Background Trigeminal neuralgia (TN) is an orofacial condition defined by reoccurring, spontaneous, short-lived but excruciating stabbing pain. Pharmacological interventions constitute the first-line treatment for TN, with antiepileptic drugs commonly prescribed. People treated for TN pain with antiepileptic drugs describe cognitive and motor difficulties affecting activities of daily living, and report poorer quality of life. We undertook the first comprehensive objective evaluation of sensorimotor and cognitive performance in participants being treated for TN pain with antiepileptic drugs relative to age-matched controls. Methods Participants (43 TN, 41 control) completed a battery of sensorimotor (steering, aiming and tracking) and cognitive (working memory, processing speed, inhibition) tasks. Results The TN group performed significantly worse than controls on the sensorimotor tracking and aiming tasks and across all cognitive measures. Conclusions The data explain why patients treated with antiepileptic drugs report impairment when conducting activities of daily living (given the need for cognitive and motor capability within most of these). The study is an important first step in: (i) ensuring there is adequate information on the impact of pharmacological treatment; (ii) identifying measures to determine optimal medication dosage and track change over time; (iii) creating an evidence base that could allow scientific justification of alternative pain treatment options for TN (e.g. the costs/benefits of surgery)
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