389 research outputs found

    Exhaust Nozzles for Supersonic Flight with Turbojet Engines

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    Good internal performance over a wide range of flight conditions can be obtained with either a plug nozzle or a variable ejector nozzle that can provide a divergent shroud at high pressure ratios. For both the ejector and the plug nozzle, external flow can sometimes cause serious drag losses and, for some plug-nozzle installations, external flow can cause serious internal performance losses. Plug-nozzle cooling and design of the secondary-air-flow systems for ejectors were also considered

    Barriers and facilitators experienced by osteopaths in implementing a biopsychosocial (BPS) framework of care when managing people with musculoskeletal pain – a mixed methods systematic review

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    BACKGROUND: Clinical practice guidelines commonly recommend adopting a biopsychosocial (BPS) framework by practitioners managing musculoskeletal pain. However, it remains unclear how osteopaths implement a BPS framework in the management of musculoskeletal pain. Hence, the objective of this review was to systematically appraise the literature on the current practices, barriers and facilitators experienced by osteopaths in implementing a BPS framework of care when managing people with musculoskeletal pain. METHODS: The following electronic databases from January 2005 to August 2020 were searched: PubMed, CINAHL, Science Direct, Google Scholar, ProQuest Central and SCOPUS. Two independent reviewers reviewed the articles retrieved from the databases to assess for eligibility. Any studies (quantitative, qualitative and mixed methods) that investigated the use or application of the BPS approach in osteopathic practice were included in the review. The critical appraisal skills program (CASP) checklist was used to appraise the qualitative studies and the Mixed Methods Appraisal Tool (MMAT) was used to appraise quantitative or mixed methods studies. Advanced convergent meta-integration was used to synthesise data from quantitative, qualitative and mixed methods studies. RESULTS: A total of 6 studies (two quantitative, three qualitative and one mixed methods) were included in the final review. While two key concepts (current practice and embracing a BPS approach) were generated using advanced meta-integration synthesis, two concepts (barriers and enablers) were informed from qualitative only data. DISCUSSION: Our review finding showed that current osteopathic practice occurs within in the biomedical model of care. Although, osteopaths are aware of the theoretical underpinnings of the BPS model and identified the need to embrace it, various barriers exist that may prevent osteopaths from implementing the BPS model in clinical practice. Ongoing education and/or workshops may be necessary to enable osteopaths to implement a BPS approach

    Are shallow-water shrimps proxies for hydrothermal-vent shrimps to assess the impact of deep-sea mining?

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    Polymetallic seafloor massive sulphide deposits are potential targets for deep-sea mining, but high concentrations of metals (including copper - Cu) may be released during exploitation activities, potentially inducing harmful impact. To determine whether shallow-water shrimp are suitable ecotoxicological proxies for deep-sea hydrothermal vent shrimp the effects of waterborne Cu exposure (3 and 10 days at 0.4 and 4 μM concentrations) in Palaemon elegans, Palaemon serratus, and Palaemon varians were compared with Mirocaris fortunata. Accumulation of Cu and a set of biomarkers were analysed. Results show different responses among congeneric species indicating that it is not appropriate to use shallow-water shrimps as ecotoxicological proxies for deep-water shrimps. During the evolutionary history of these species they were likely subject to different chemical environments which may have induced different molecular/biochemical adaptations/tolerances. Results highlight the importance of analysing effects of deep-sea mining in situ and in local species to adequately assess ecotoxicological effects under natural environmental conditions.This work was developed under the MIDAS project (Managing im-pacts of deep-sea resource exploitation), funded by the EuropeanCommission, European Union, 7th Framework Programme under thetheme“Sustainable management of Europe's deep sea and sub-seafloorresources”(Grant Agreement 603418). This work was also supported bythe Fundação para a Ciência e Tecnologia I.P. Portugal (FCT) and theDireção-Geral de Política do Mar (DGPM), Portugal through the projectMining2/2017/001–MiningImpact 2 (JPI Oceans), and FCT furtherfunded the grants CEECIND005262017 and UID/MAR/00350/2013.We acknowledge the captains and crews of the oceanographic ship“Pourquoi Pas?”, and the pilots of Victor 6000 Remotely OperatedVehicle, for their dedicated assistance during sampling of vent shrimps.We are also grateful to F. Lallier, chief scientist of the Biobaz cruise. Wewould like to warmly thank Océanopolis staffmembers, J-M Carré, SDelaporte and O Gouello, for their important contributions to shrimpmaintenance.info:eu-repo/semantics/publishedVersio

    Tomato protoplast DNA transformation: physical linkage and recombination of exogenous DNA sequences

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    Tomato protoplasts have been transformed with plasmid DNA's, containing a chimeric kanamycin resistance gene and putative tomato origins of replication. A calcium phosphate-DNA mediated transformation procedure was employed in combination with either polyethylene glycol or polyvinyl alcohol. There were no indications that the tomato DNA inserts conferred autonomous replication on the plasmids. Instead, Southern blot hybridization analysis of seven kanamycin resistant calli revealed the presence of at least one kanamycin resistance locus per transformant integrated in the tomato nuclear DNA. Generally one to three truncated plasmid copies were found integrated into the tomato nuclear DNA, often physically linked to each other. For one transformant we have been able to use the bacterial ampicillin resistance marker of the vector plasmid pUC9 to 'rescue' a recombinant plasmid from the tomato genome. Analysis of the foreign sequences included in the rescued plasmid showed that integration had occurred in a non-repetitive DNA region. Calf-thymus DNA, used as a carrier in transformation procedure, was found to be covalently linked to plasmid DNA sequences in the genomic DNA of one transformant. A model is presented describing the fate of exogenously added DNA during the transformation of a plant cell. The results are discussed in reference to the possibility of isolating DNA sequences responsible for autonomous replication in tomato.

    New technologies for 3D realization in Art and Design practice

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    As digital design technologies become ever more widespread, CAD-CAM, virtual and rapid prototyping techniques are increasingly being exploited by creative practitioners working in areas outside the industrial design and engineering contexts in which these technologies are currently predominantly employed. This review paper aims to critically examine work by artists, craft practitioners, and designer-makers who creatively engage with these new and rapidly emerging technologies and, by doing so, extend their own practice and push at the boundaries of art and design disciplines. Historic precedents for new 3D technologies in the fine and applied arts are identified, and writing by Heidegger, Baudrillard, and Virilio informs the critical review of work by art and design practitioners in sculpture, metalwork, jewellery, and ceramics. The discussion reflects on relationships between art and technology and physical and virtual making, and concludes by pointing to the possibility of new “hybrid” forms of practice which bridge the gap between physical and virtual design worlds. The paper closes by suggesting that the notion of “truth to materials” in the arts and crafts might now be extended to one of “truth to virtual materials”, as practitioners creatively negotiate relationships between digital cause and physical effect

    Barriers and facilitators experienced by osteopaths in implementing a biopsychosocial (BPS) framework of care when managing people with musculoskeletal pain – A mixed methods systematic review protocol

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    Background: Musculoskeletal (MSK) pain conditions have a substantial influence on the quality of life. Psychosocial factors such as depression, anxiety and social isolation have been shown to play an important role in the development and management of MSK pain. Therefore, clinical practice guidelines commonly recommend adopting a biopsychosocial (BPS) framework by practitioners managing MSK pain. However, it remains unclear how osteopaths implement a BPS framework in the management of MSK pain. This protocol describes the objective and methods of a systematic review of barriers and facilitators experienced by osteopaths in implementing a BPS framework of care when managing people with MSK pain. Methods: The following electronic databases from January 2005 to March 2019 will be searched: PubMed, AMED, EMBASE, CINAHL, Cochrane Library, Physiotherapy Evidence Database (PEDro), and SCOPUS. Two independent reviewers will review the title, abstract and full-text article retrieved from the databases to assess potentially eligible studies. Any studies (quantitative, qualitative and mixed methods) that investigated the use or application of the biopsychosocial approach in osteopathic practice will be included in the review. Data synthesis for qualitative studies will be done using the GRADE‐CERQual tool. Data synthesis methods for mixed method studies will be decided after data extraction and assessment. Discussion: This systematic review will provide critical insights into the barriers and facilitators experienced by osteopaths to implement the BPS framework in their practice. This may be important and timely as a BPS framework has been recommended by various clinical practice guidelines. © 2020 Elsevier Lt
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