35 research outputs found

    Comparison of the Sentinel-3A and B SLSTR Tandem Phase Data using metrological principles

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    The Sentinel 3 mission is part of the Copernicus programme space segment and has the objective of making global operational observations of ocean and land parameters with its four onboard sensors. Two Sentinel 3 satellites are currently on orbit, providing near-daily global coverage. Sentinel 3A was launched on 16 February 2016 and Sentinel 3B on 25 April 2018. For the early part of its operation, Sentinel 3B flew in tandem with Sentinel 3A, flying 30 seconds ahead of its twin mission. This provided a unique opportunity to compare the instruments on the two satellites, and to test the per pixel uncertainty values in a metrologically-robust manner. In this work we consider the tandem-phase data from the infrared channels of one of the onboard instruments: the Sea and Land Surface Temperature Radiometer, SLSTR. A direct comparison was made of both the Level 1 radiance values and the Level 2 sea surface temperature values derived from those radiances. At Level 1 the distribution of differences between the sensor values were compared to the declared uncertainties for data gridded on to a regular latitude-longitude grid with propagated pixel uncertainties. The results showed good overall radiometric agreement between the two sensors, with mean differences of ∟0.06 K, although there was a scene-temperature dependent difference for the oblique view that was consistent with what was expected from a stray light effect observed pre-flight. We propose a means to correct for this effect based on the tandem data. Level 1 uncertainties were found to be representative of the variance of the data, expect in those channels affected by the stray light effect. The sea surface temperature results show a very small difference between the sensors that could be in part due to the fact that the Sentinel-3A retrieval coefficients were also applied to the Sentinel-3B retrieval because the Sentinel-3B coefficients are not currently available. This will lead to small errors between the S3A and S3B retrievals. The comparison also suggests that the retrieval uncertainties may need updating for two of the retrieval processes, that there are extra components of uncertainty related the quality level and the probability of cloud that should be included. Finally, a study of the quality flags assigned to sea surface temperature pixel values provided valuable insight into the origin of those quality levels and highlighted possible uncertainties in the defined quality level

    Securing All intraVenous devices Effectively in hospitalised patients—the SAVE trial: study protocol for a multicentre randomised controlled trial

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    Introduction: Over 70% of all hospital admissions have a peripheral intravenous device (PIV) inserted; however, the failure rate of PIVs is unacceptably high, with up to 69% of these devices failing before treatment is complete. Failure can be due to dislodgement, phlebitis, occlusion/infiltration and/or infection. This results in interrupted medical therapy; painful phlebitis and reinsertions; increased hospital length of stay, morbidity and mortality from infections; and wasted medical/nursing time. Appropriate PIV dressing and securement may prevent many cases of PIV failure, but little comparative data exist regarding the efficacy of various PIV dressing and securement methods. This trial will investigate the clinical and cost-effectiveness of 4 methods of PIV dressing and securement in preventing PIV failure. Methods and analysis: A multicentre, parallel group, superiority randomised controlled trial with 4 arms, 3 experimental groups (tissue adhesive, bordered polyurethane dressing, sutureless securement device) and 1 control (standard polyurethane dressing) is planned. There will be a 3-year recruitment of 1708 adult patients, with allocation concealment until randomisation by a centralised web-based service. The primary outcome is PIV failure which includes any of: dislodgement, occlusion/infiltration, phlebitis and infection. Secondary outcomes include: types of PIV failure, PIV dwell time, costs, device colonisation, skin colonisation, patient and staff satisfaction. Relative incidence rates of device failure per 100 devices and per 1000 device days with 95% CIs will summarise the impact of each dressing, and test differences between groups. Kaplan-Meier survival curves (with log-rank Mantel-Cox test) will compare device failure over time. p Values of <0.05 will be considered significant. Secondary end points will be compared between groups using parametric or non-parametric techniques appropriate to level of measurement

    Acetyl-11-keto-β-boswellic acid (AKBA); targeting oral cavity pathogens

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    <p>Abstract</p> <p>Background</p> <p>Boswellic acids mixture of triterpenic acids obtained from the oleo gum resin of <it>Boswellia serrata </it>and known for its effectiveness in the treatment of chronic inflammatory disease including peritumor edema. Boswellic acids have been extensively studied for a number of activities including anti inflammatory, antitumor, immunomodulatory, and inflammatory bowel diseases. The present study describes the antimicrobial activities of boswellic acid molecules against oral cavity pathogens. Acetyl-11-keto-β-boswellic acid (AKBA), which exhibited the most potent antibacterial activity, was further evaluated in time kill studies, mutation prevention frequency, postantibiotic effect (PAE) and biofilm susceptibility assay against oral cavity pathogens.</p> <p>Findings</p> <p>AKBA exhibited an inhibitory effect on all the oral cavity pathogens tested (MIC of 2-4 μg/ml). It exhibited concentration dependent killing of S<it>treptococcus mutans </it>ATCC 25175 up to 8 × MIC and also prevented the emergence of mutants of <it>S.mutans </it>ATCC 25175 at 8× MIC. AKBA demonstrated postantibiotic effect (PAE) of 5.7 ± 0.1 h at 2 × MIC. Furthermore, AKBA inhibited the formation of biofilms generated by <it>S.mutans </it>and <it>Actinomyces viscosus </it>and also reduced the preformed biofilms by these bacteria.</p> <p>Conclusions</p> <p>AKBA can be useful compound for the development of antibacterial agent against oral pathogens and it has great potential for use in mouthwash for preventing and treating oral infections.</p

    Vilhelm Lundstedt’s ‘Legal Machinery’ and the Demise of Juristic Practice

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    This article aims to contribute to the academic debate on the general crisis faced by law schools and the legal professions by discussing why juristic practice is a matter of experience rather than knowledge. Through a critical contextualisation of Vilhelm Lundstedt’s thought under processes of globalisation and transnationalism, it is argued that the demise of the jurist’s function is related to law’s scientification as brought about by the metaphysical construction of reality. The suggested roadmap will in turn reveal that the current voiding of juristic practice and its teaching is part of the crisis regarding what makes us human

    Are novel ecosystems the only novelty of rewilding?

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    Since the introduction of the term “rewilding” in 1998, several definitions have been proposed, sparking debate around terminology and how (or if) rewilding differs from restoration. Many papers attempt to distinguish between the two terms through a series of descriptive attributes: historic baselines, landscape-driven transformation, ongoing human intervention, the connection of people with nature, and the creation of novel ecosystems. Here, we discuss the overlap between these terms and illustrate that the creation of novel ecosystems provides the clearest distinction between rewilding and restoration. If the definition of rewilding is distilled down to its most unique component, the creation of novel ecosystems, perhaps scientists can then work to produce a clear framework for rewilding that is based on best conservation practice.https://onlinelibrary.wiley.com/journal/1526100xhj2021Mammal Research Institut
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