3 research outputs found

    Spatiotemporal Video Quality Assessment Method via Multiple Feature Mappings

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    Progressed video quality assessment (VQA) methods aim to evaluate the perceptual quality of videos in many applications but often prompt to increase computational complexity. Problems derive from the complexity of the distorted videos that are of significant concern in the communication industry, as well as the spatial-temporal content of the two-fold (spatial and temporal) distortion. Therefore, the findings of the study indicate that the information in the spatiotemporal slice (STS) images are useful in measuring video distortion. This paper mainly focuses on developing on a full reference video quality assessment algorithm estimator that integrates several features of spatiotemporal slices (STSS) of frames to form a high-performance video quality. This research work aims to evaluate video quality by utilizing several VQA databases by the following steps: (1) we first arrange the reference and test video sequences into a spatiotemporal slice representation. A collection of spatiotemporal feature maps were computed on each reference-test video. These response features are then processed by using a Structural Similarity (SSIM) to form a local frame quality.  (2) To further enhance the quality assessment, we combine the spatial feature maps with the spatiotemporal feature maps and propose the VQA model, named multiple map similarity feature deviation (MMSFD-STS). (3) We apply a sequential pooling strategy to assemble the quality indices of frames in the video quality scoring. (4) Extensive evaluations on video quality databases show that the proposed VQA algorithm achieves better/competitive performance as compared with other state- of- the- art methods

    Comparative efficacy of low-dose versus standard-dose azithromycin for patients with yaws: a randomised non-inferiority trial in Ghana and Papua New Guinea

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    Summary: Background: A dose of 30 mg/kg of azithromycin is recommended for treatment of yaws, a disease targeted for global eradication. Treatment with 20 mg/kg of azithromycin is recommended for the elimination of trachoma as a public health problem. In some settings, these diseases are co-endemic. We aimed to determine the efficacy of 20 mg/kg of azithromycin compared with 30 mg/kg azithromycin for the treatment of active and latent yaws. Methods: We did a non-inferiority, open-label, randomised controlled trial in children aged 6–15 years who were recruited from schools in Ghana and schools and the community in Papua New Guinea. Participants were enrolled based on the presence of a clinical lesion that was consistent with infectious primary or secondary yaws and a positive rapid diagnostic test for treponemal and non-treponemal antibodies. Participants were randomly assigned (1:1) to receive either standard-dose (30 mg/kg) or low-dose (20 mg/kg) azithromycin by a computer-generated random number sequence. Health-care workers assessing clinical outcomes in the field were not blinded to the patient's treatment, but investigators involved in statistical or laboratory analyses and the participants were blinded to treatment group. We followed up participants at 4 weeks and 6 months. The primary outcome was cure at 6 months, defined as lesion healing at 4 weeks in patients with active yaws and at least a four-fold decrease in rapid plasma reagin titre from baseline to 6 months in patients with active and latent yaws. Active yaws was defined as a skin lesion that was positive for Treponema pallidum ssp pertenue in PCR testing. We used a non-inferiority margin of 10%. This trial was registered with ClinicalTrials.gov, number NCT02344628. Findings: Between June 12, 2015, and July 2, 2016, 583 (65·1%) of 895 children screened were enrolled; 292 patients were assigned a low dose of azithromycin and 291 patients were assigned a standard dose of azithromycin. 191 participants had active yaws and 392 had presumed latent yaws. Complete follow-up to 6 months was available for 157 (82·2%) of 191 patients with active yaws. In cases of active yaws, cure was achieved in 61 (80·3%) of 76 patients in the low-dose group and in 68 (84·0%) of 81 patients in the standard-dose group (difference 3·7%; 95% CI −8·4 to 15·7%; this result did not meet the non-inferiority criterion). There were no serious adverse events reported in response to treatment in either group. The most commonly reported adverse event at 4 weeks was gastrointestinal upset, with eight (2·7%) participants in each group reporting this symptom. Interpretation: In this study, low-dose azithromycin did not meet the prespecified non-inferiority margin compared with standard-dose azithromycin in achieving clinical and serological cure in PCR-confirmed active yaws. Only a single participant (with presumed latent yaws) had definitive serological failure. This work suggests that 20 mg/kg of azithromycin is probably effective against yaws, but further data are needed. Funding: Coalition for Operational Research on Neglected Tropical Diseases

    Exploring the cost-effectiveness of high versus low perioperative fraction of inspired oxygen in the prevention of surgical site infections among abdominal surgery patients in three low- and middle-income countries

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    Background: This study assessed the potential cost-effectiveness of high (80–100%) vs low (21–35%) fraction of inspired oxygen (FiO2) at preventing surgical site infections (SSIs) after abdominal surgery in Nigeria, India, and South Africa. Methods: Decision-analytic models were constructed using best available evidence sourced from unbundled data of an ongoing pilot trial assessing the effectiveness of high FiO2, published literature, and a cost survey in Nigeria, India, and South Africa. Effectiveness was measured as percentage of SSIs at 30 days after surgery, a healthcare perspective was adopted, and costs were reported in US dollars ().Results:HighFiO2maybecosteffective(cheaperandeffective).InNigeria,theaveragecostforhighFiO2was). Results: High FiO2 may be cost-effective (cheaper and effective). In Nigeria, the average cost for high FiO2 was 216 compared with 222forlowFiO2leadingtoa 222 for low FiO2 leading to a −6 (95% confidence interval [CI]: −13to 13 to −1) difference in costs. In India, the average cost for high FiO2 was 184comparedwith184 compared with 195 for low FiO2 leading to a −11(9511 (95% CI: −15 to −6)differenceincosts.InSouthAfrica,theaveragecostforhighFiO2was6) difference in costs. In South Africa, the average cost for high FiO2 was 1164 compared with 1257forlowFiO2leadingtoa 1257 for low FiO2 leading to a −93 (95% CI: −132to 132 to −65) difference in costs. The high FiO2 arm had few SSIs, 7.33% compared with 8.38% for low FiO2, leading to a −1.05 (95% CI: −1.14 to −0.90) percentage point reduction in SSIs. Conclusion: High FiO2 could be cost-effective at preventing SSIs in the three countries but further data from large clinical trials are required to confirm this
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