7 research outputs found

    Diagnostic accuracy of contrast-enhanced CT for neck abscesses : A systematic review and meta-analysis of positive predictive value

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    Objectives To review the diagnostic accuracy of contrast-enhanced computed tomography (CT) in differentiating abscesses from cellulitis in patients with neck infections, using surgical findings as the reference standard. Materials and methods Previous studies in the last 32 years were searched from PubMed and Embase. Because of partial verification bias (only positive abscess findings are usually verified surgically), sensitivity and specificity estimates are unreliable, and we focused on positive predictive value (PPV). For all studies, PPV was calculated as the proportion of true positives out of all positives on imaging. To estimate pooled PPV, we used both the median with an interquartile range and a model-based estimate. For narrative purposes, we reviewed the utility of common morphological CT criteria for abscesses, such as central hypodensity, the size of the collection, bulging, rim enhancement, and presence of air, as well as sensitivity and specificity values reported by the original reports. Results 23 studies were found reporting 1453 patients, 14 studies in children (771 patients), two in adults (137 patients), and seven including all ages (545 patients). PPV ranged from 0.67 to 0.97 in individual studies, had a median of 0.84 (0.79–0.87), and a model-based pooled estimate of 0.83 (95% confidence interval 0.80–0.85). Most morphological CT criteria had considerable overlap between abscesses and cellulitis. Conclusions The pooled estimate of PPV is 0.83 for diagnosing neck abscesses with CT. False positives may be due to limited soft tissue contrast resolution. Overall, none of the morphological criteria seem to be highly accurate for differentiation between abscess and cellulitis.© 2022 Hagelberg et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.fi=vertaisarvioitu|en=peerReviewed

    Diagnostic accuracy of contrast-enhanced CT for neck abscesses: A systematic review and meta-analysis of positive predictive value

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    ObjectivesTo review the diagnostic accuracy of contrast-enhanced computed tomography (CT) in differentiating abscesses from cellulitis in patients with neck infections, using surgical findings as the reference standard.Materials and methodsPrevious studies in the last 32 years were searched from PubMed and Embase. Because of partial verification bias (only positive abscess findings are usually verified surgically), sensitivity and specificity estimates are unreliable, and we focused on positive predictive value (PPV). For all studies, PPV was calculated as the proportion of true positives out of all positives on imaging. To estimate pooled PPV, we used both the median with an interquartile range and a model-based estimate. For narrative purposes, we reviewed the utility of common morphological CT criteria for abscesses, such as central hypodensity, the size of the collection, bulging, rim enhancement, and presence of air, as well as sensitivity and specificity values reported by the original reports.Results23 studies were found reporting 1453 patients, 14 studies in children (771 patients), two in adults (137 patients), and seven including all ages (545 patients). PPV ranged from 0.67 to 0.97 in individual studies, had a median of 0.84 (0.79–0.87), and a model-based pooled estimate of 0.83 (95% confidence interval 0.80–0.85). Most morphological CT criteria had considerable overlap between abscesses and cellulitis.ConclusionsThe pooled estimate of PPV is 0.83 for diagnosing neck abscesses with CT. False positives may be due to limited soft tissue contrast resolution. Overall, none of the morphological criteria seem to be highly accurate for differentiation between abscess and cellulitis.</p

    Three Saturn-mass planets transiting F-type stars revealed with TESS and HARPS

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    While the sample of confirmed exoplanets continues to increase, the population of transiting exoplanets around early-type stars is still limited. These planets allow us to investigate the planet properties and formation pathways over a wide range of stellar masses and study the impact of high irradiation on hot Jupiters orbiting such stars. We report the discovery of TOI-615b, TOI-622b, and TOI-2641b, three Saturn-mass planets transiting main sequence, F-type stars. The planets were identified by the Transiting Exoplanet Survey Satellite (TESS) and confirmed with complementary ground-based and radial velocity observations. TOI-615b is a highly irradiated (∌\sim1277 F⊕F_{\oplus}) and bloated Saturn-mass planet (1.69−0.06+0.05^{+0.05}_{-0.06}RJupR_{Jup} and 0.43−0.08+0.09^{+0.09}_{-0.08}MJupM_{Jup}) in a 4.66 day orbit transiting a 6850 K star. TOI-622b has a radius of 0.82−0.03+0.03^{+0.03}_{-0.03}RJupR_{Jup} and a mass of 0.30−0.08+0.07^{+0.07}_{-0.08}~MJupM_{Jup} in a 6.40 day orbit. Despite its high insolation flux (∌\sim600 F⊕F_{\oplus}), TOI-622b does not show any evidence of radius inflation. TOI-2641b is a 0.37−0.04+0.05^{+0.05}_{-0.04}MJupM_{Jup} planet in a 4.88 day orbit with a grazing transit (b = 1.04−0.06+0.05^{+0.05}_{-0.06 }) that results in a poorly constrained radius of 1.61−0.64+0.46^{+0.46}_{-0.64}RJupR_{Jup}. Additionally, TOI-615b is considered attractive for atmospheric studies via transmission spectroscopy with ground-based spectrographs and JWST\textit{JWST}. Future atmospheric and spin-orbit alignment observations are essential since they can provide information on the atmospheric composition, formation and migration of exoplanets across various stellar types.Comment: 16 pages, 17 figures, submitted to A&

    Getting ready for REDD+ in Tanzania: a case study of progress and challenges

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    The proposed mechanism for Reducing Emissions from Deforestation and Degradation (REDD+) offers significant potential for conserving forests to reduce negative impacts of climate change. Tanzania is one of nine pilot countries for the United Nations REDD Programme, receives significant funding from the Norwegian, Finnish and German governments and is a participant in the World Bank’s Forest Carbon Partnership Facility. In combination, these interventions aim to mitigate greenhouse gas emissions, provide an income to rural communities and conserve biodiversity. The establishment of the UN-REDD Programme in Tanzania illustrates real-world challenges in a developing country. These include currently inadequate baseline forestry data sets (needed to calculate reference emission levels), inadequate government capacity and insufficient experience of implementing REDD+-type measures at operational levels. Additionally, for REDD+ to succeed, current users of forest resources must adopt new practices, including the equitable sharing of benefits that accrue from REDD+ implementation. These challenges are being addressed by combined donor support to implement a national forest inventory, remote sensing of forest cover, enhanced capacity for measuring, reporting and verification, and pilot projects to test REDD+ implementation linked to the existing Participatory Forest Management Programme. Our conclusion is that even in a country with considerable donor support, progressive forest policies, laws and regulations, an extensive network of managed forests and increasingly developed locally-based forest management approaches, implementing REDD+ presents many challenges. These are being met by coordinated, genuine partnerships between government, non-government and community-based agencie

    Three Saturn-mass planets transiting F-type stars revealed with TESS and HARPS⋆ TOI-615b, TOI-622b, and TOI-2641b

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    While the sample of confirmed exoplanets continues to increase, the population of transiting exoplanets around early-type stars is still limited. These planets allow us to investigate the planet properties and formation pathways over a wide range of stellar masses and study the impact of high irradiation on hot Jupiters orbiting such stars. We report the discovery of TOI-615b, TOI-622b, and TOI-2641b, three Saturn-mass planets transiting main sequence, F-type stars. The planets were identified by the Transiting Exoplanet Survey Satellite (TESS) and confirmed with complementary ground-based and radial velocity observations. TOI-615b is a highly irradiated (∌1277 F⊕) and bloated Saturn-mass planet (1.69+0.05−0.06RJup and 0.43+0.09−0.08MJup) in a 4.66 day orbit transiting a 6850 K star. TOI-622b has a radius of 0.82+0.03−0.03RJup and a mass of 0.30+0.07−0.08~MJup in a 6.40 day orbit. Despite its high insolation flux (∌600 F⊕), TOI-622b does not show any evidence of radius inflation. TOI-2641b is a 0.37+0.05−0.04MJup planet in a 4.88 day orbit with a grazing transit (b = 1.04+0.05−0.06) that results in a poorly constrained radius of 1.61+0.46−0.64RJup. Additionally, TOI-615b is considered attractive for atmospheric studies via transmission spectroscopy with ground-based spectrographs and JWST. Future atmospheric and spin-orbit alignment observations are essential since they can provide information on the atmospheric composition, formation and migration of exoplanets across various stellar types
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