200 research outputs found

    The Asian red seaweed Grateloupia turuturu (Rhodophyta) invades the Gulf of Maine

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    We report the invasion of the Gulf of Maine, in the northwest Atlantic Ocean, by the largest red seaweed in the world, the Asian Grateloupia turuturu. First detected in 1994 in Narragansett Bay, Rhode Island, south of Cape Cod, this alga had expanded its range in the following years only over to Long Island and into Long Island Sound. In July 2007 we found Grateloupia in the Cape Cod Canal and as far north (east) as Boston, Massachusetts, establishing its presence in the Gulf of Maine. Grateloupia can be invasive and may be capable of disrupting low intertidal and shallow subtidal seaweeds. The plant\u27s broad physiological tolerances suggest that it will be able to expand possibly as far north as the Bay of Fundy. We predict its continued spread in North America and around the world, noting that its arrival in the major international port of Boston may now launch G. turuturu on to new global shipping corridors

    Curved Gratings as Plasmonic Lenses for Linearly Polarised Light

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    The ability of curved gratings as sectors of concentric circular gratings to couple linearly polarized light into focused surface plasmons is investigated by theory, simulation and experiment. Curved gratings, as sectors of concentric circular gratings with four different sector angles, are etched into a 30-nm thick gold layer on a glass coverslip and used to couple linearly-polarised free space light at nm into surface plasmons. The experimental and simulation results show that increasing the sector angle of the curved gratings decreases the lateral spotsize of the excited surface plasmons, resulting in focussing of surface plasmons which is analogous to the behaviour of classical optical lenses. We also show that two faced curved gratings, with their groove radius mismatched by half of the plasmon wavelength (asymmetric configuration), can couple linearly-polarised light into a single focal spot of concentrated surface plasmons with smaller depth of focus and higher intensity in comparison to single-sided curved gratings. The major advantage of these structures is the coupling of linearly-polarised light into focused surface plasmons with access to and control of the plasmon focal spot, which facilitates potential applications in sensing, detection and nonlinear plasmonics.Comment: 15 pages and 12 figure

    Build your own virtual photonics communication system: a Photonics Simulator for high school students

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    In our community outreach activities, we have been developing teaching tools to inform high school students about Optics and Photonics. While there is research supporting the idea that incorporating computer games into education can create a ‘strong cognitive effect’, others suggest that games should merely be used as a teaching tool, rather than as a primary vehicle for teaching. Thus we chose to develop an open-ended Photonics Simulator using Flash, employing photonic components as building blocks to form a communications system, within a classroom lesson including an illustrated talk with a simple optical fibre demonstration. The virtual photonics components have the same properties as the devices used in actual telecommunications links and in our research laboratories. The software is available to download. We trialled the Photonics Simulator during a single lesson (lessons ranged from 50 minutes to 90 minutes) with five Year 9 or Year 10 classes (from three schools - coeducational, girls only and boys only) during 2007. We gave them a short survey before the lesson to establish their level of knowledge of photonics, and then administered a slightly longer survey, including some repeated questions, after the lesson. The level of knowledge of photonics was significantly improved in every class and in every subgroup tested. (For example answers on ‘the function of an optical amplifier’ improved from 40% correct/partly correct to 70% correct/partly correct). Furthermore, the ‘hands-on’ nature of the simulator was effective in engaging the students, (94% ‘enjoyed playing the game’) and showing them the basis of the communications systems that underpin the Internet

    Deviation from STEM Peers and Employers in Employability Focuses: the Case of Maths, Stats, Physics and Astronomy Students

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    STEM employability is a non-homogenous phenomenon with mixed outcomes for graduates from different disciplines. A myriad of factors may contribute to the diverse employability. Here we examine the heterogeneity of career and employability development focuses among different STEM student cohorts in the curricular context. We utilised a structured framework of Career Information Literacy (CIL) to map career and employability focuses of STEM students and employers. This paper presents findings from the Mathematics, Statistics, Physics and Astronomy cohort. Data was collected from final year capstone unit students at a STEM faculty in an Australian university (N=517, response rate 44%). Of which, Maths, Stats, Physics and Astronomy (MSPA) students were analysed as a cohort (N=80, response rate 73%). Concurrent data collection took place with STEM employers and industry stakeholders who engaged this faculty in recruitment and employability activities (N=62, response rate 78%). Upon comparing student cohorts’ focuses on career and employability development with their peers and employers, we found MSPA students differ from both their STEM peers and employers. Most other STEM student cohorts differ from employers, but not their peers. The implications point to a different career development need of this cohort to fully realise the benefits of their STEM education

    A “Learning Revolution”? Investigating Pedagogic Practices around Interactive Whiteboards in British Primary Classrooms

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    Interactive whiteboards have been rapidly introduced into all primary schools under UK Government initiatives. These large, touch-sensitive screens, which control a computer connected to a digital projector, seem to be the first type of educational technology particularly suited for whole-class teaching and learning. Strong claims are made for their value by manufacturers and policy makers, but there has been little research on how, if at all, they influence established pedagogic practices, communicative processes and educational goals. This study has been designed to examine this issue, using observations in primary (elementary) school classrooms. It is funded by the UK Economic and Social Research Council and builds on the authors’ previous research on ICT in educational dialogues and collaborative activities

    Do Termites Avoid Carcasses? Behavioral Responses Depend on the Nature of the Carcasses

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    BACKGROUND: Undertaking behavior is a significant adaptation to social life in enclosed nests. Workers are known to remove dead colony members from the nest. Such behavior prevents the spread of pathogens that may be detrimental to a colony. To date, little is known about the ethological aspects of how termites deal with carcasses. METHODOLOGY AND PRINCIPAL FINDINGS: In this study, we tested the responses to carcasses of four species from different subterranean termite taxa: Coptotermes formosanus Shiraki and Reticulitermes speratus (Kolbe) (lower termites) and Microcerotermes crassus Snyder and Globitermes sulphureus Haviland (higher termites). We also used different types of carcasses (freshly killed, 1-, 3-, and 7-day-old, and oven-killed carcasses) and mutilated nestmates to investigate whether the termites exhibited any behavioral responses that were specific to carcasses in certain conditions. Some behavioral responses were performed specifically on certain types of carcasses or mutilated termites. C. formosanus and R. speratus exhibited the following behaviors: (1) the frequency and time spent in antennating, grooming, and carcass removal of freshly killed, 1-day-old, and oven-killed carcasses were high, but these behaviors decreased as the carcasses aged; (2) the termites repeatedly crawled under the aging carcass piles; and (3) only newly dead termites were consumed as a food source. In contrast, M. crassus and G. sulphureus workers performed relatively few behavioral acts. Our results cast a new light on the previous notion that termites are necrophobic in nature. CONCLUSION: We conclude that the behavioral response towards carcasses depends largely on the nature of the carcasses and termite species, and the response is more complex than was previously thought. Such behavioral responses likely are associated with the threat posed to the colony by the carcasses and the feeding habits and nesting ecology of a given species

    Abstracts from the NIHR INVOLVE Conference 2017

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    Variation in Structure and Process of Care in Traumatic Brain Injury: Provider Profiles of European Neurotrauma Centers Participating in the CENTER-TBI Study.

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    INTRODUCTION: The strength of evidence underpinning care and treatment recommendations in traumatic brain injury (TBI) is low. Comparative effectiveness research (CER) has been proposed as a framework to provide evidence for optimal care for TBI patients. The first step in CER is to map the existing variation. The aim of current study is to quantify variation in general structural and process characteristics among centers participating in the Collaborative European NeuroTrauma Effectiveness Research in Traumatic Brain Injury (CENTER-TBI) study. METHODS: We designed a set of 11 provider profiling questionnaires with 321 questions about various aspects of TBI care, chosen based on literature and expert opinion. After pilot testing, questionnaires were disseminated to 71 centers from 20 countries participating in the CENTER-TBI study. Reliability of questionnaires was estimated by calculating a concordance rate among 5% duplicate questions. RESULTS: All 71 centers completed the questionnaires. Median concordance rate among duplicate questions was 0.85. The majority of centers were academic hospitals (n = 65, 92%), designated as a level I trauma center (n = 48, 68%) and situated in an urban location (n = 70, 99%). The availability of facilities for neuro-trauma care varied across centers; e.g. 40 (57%) had a dedicated neuro-intensive care unit (ICU), 36 (51%) had an in-hospital rehabilitation unit and the organization of the ICU was closed in 64% (n = 45) of the centers. In addition, we found wide variation in processes of care, such as the ICU admission policy and intracranial pressure monitoring policy among centers. CONCLUSION: Even among high-volume, specialized neurotrauma centers there is substantial variation in structures and processes of TBI care. This variation provides an opportunity to study effectiveness of specific aspects of TBI care and to identify best practices with CER approaches

    Variation in general supportive and preventive intensive care management of traumatic brain injury: a survey in 66 neurotrauma centers participating in the Collaborative European NeuroTrauma Effectiveness Research in Traumatic Brain Injury (CENTER-TBI) study

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    Abstract Background General supportive and preventive measures in the intensive care management of traumatic brain injury (TBI) aim to prevent or limit secondary brain injury and optimize recovery. The aim of this survey was to assess and quantify variation in perceptions on intensive care unit (ICU) management of patients with TBI in European neurotrauma centers. Methods We performed a survey as part of the Collaborative European NeuroTrauma Effectiveness Research in Traumatic Brain Injury (CENTER-TBI) study. We analyzed 23 questions focused on: 1) circulatory and respiratory management; 2) fever control; 3) use of corticosteroids; 4) nutrition and glucose management; and 5) seizure prophylaxis and treatment. Results The survey was completed predominantly by intensivists (n = 33, 50%) and neurosurgeons (n = 23, 35%) from 66 centers (97% response rate). The most common cerebral perfusion pressure (CPP) target was > 60 mmHg (n = 39, 60%) and/or an individualized target (n = 25, 38%). To support CPP, crystalloid fluid loading (n = 60, 91%) was generally preferred over albumin (n = 15, 23%), and vasopressors (n = 63, 96%) over inotropes (n = 29, 44%). The most commonly reported target of partial pressure of carbon dioxide in arterial blood (PaCO2) was 36–40 mmHg (4.8–5.3 kPa) in case of controlled intracranial pressure (ICP) < 20 mmHg (n = 45, 69%) and PaCO2 target of 30–35 mmHg (4–4.7 kPa) in case of raised ICP (n = 40, 62%). Almost all respondents indicated to generally treat fever (n = 65, 98%) with paracetamol (n = 61, 92%) and/or external cooling (n = 49, 74%). Conventional glucose management (n = 43, 66%) was preferred over tight glycemic control (n = 18, 28%). More than half of the respondents indicated to aim for full caloric replacement within 7 days (n = 43, 66%) using enteral nutrition (n = 60, 92%). Indications for and duration of seizure prophylaxis varied, and levetiracetam was mostly reported as the agent of choice for both seizure prophylaxis (n = 32, 49%) and treatment (n = 40, 61%). Conclusions Practice preferences vary substantially regarding general supportive and preventive measures in TBI patients at ICUs of European neurotrauma centers. These results provide an opportunity for future comparative effectiveness research, since a more evidence-based uniformity in good practices in general ICU management could have a major impact on TBI outcome
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