174 research outputs found

    Performance evaluation of filament wound tubes after long term exposure to aggressive environments

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    Performance evaluation of filament wound fiberglass/vinyl ester tubes, incorporating either glass veil or PVC corrosion liners, which were exposed to water (different temperatures), air, HCl, and sulfuric acid

    Automatic image quality assessment and measurement of fetal head in two-dimensional ultrasound image

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    Owing to the inconsistent image quality existing in routine obstetric ultrasound (US) scans that leads to a large intraobserver and interobserver variability, the aim of this study is to develop a quality-assured, fully automated US fetal head measurement system. A texton-based fetal head segmentation is used as a prerequi- site step to obtain the head region. Textons are calculated using a filter bank designed specific for US fetal head structure. Both shape- and anatomic-based features calculated from the segmented head region are then fed into a random forest classifier to determine the quality of the image (e.g., whether the image is acquired from a correct imaging plane), from which fetal head measurements [biparietal diameter (BPD), occipital–frontal diam- eter (OFD), and head circumference (HC)] are derived. The experimental results show a good performance of our method for US quality assessment and fetal head measurements. The overall precision for automatic image quality assessment is 95.24% with 87.5% sensitivity and 100% specificity, while segmentation performance shows 99.27% (`0.26) of accuracy, 97.07% (`2.3) of sensitivity, 2.23 mm (`0.74) of the maximum symmetric contour distance, and 0.84 mm (`0.28) of the average symmetric contour distance. The statistical analysis results using paired t-test and Bland–Altman plots analysis indicate that the 95% limits of agreement for inter observer variability between the automated measurements and the senior expert measurements are 2.7 mm of BPD, 5.8 mm of OFD, and 10.4 mm of HC, whereas the mean differences are −0.038 ` 1.38 mm, −0.20 ` 2.98 mm, and −0.72 ` 5.36 mm, respectively. These narrow 95% limits of agreements indicate a good level of consistency between the automated and the senior expert’s measurements

    The essential role of other effective area-based conservation measures in achieving big bold conservation targets

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    Continued biodiversity loss has prompted calls for half of the planet to be set aside for nature - including E. O Wilson's "Half-Earth" approach and the Wild Foundation's "Nature Needs Half" initiative. These efforts have provided a necessary wake-up call and drawn welcome global attention for the urgent need for increased action on conserving biodiversity and nature in general. Yet they have also sparked debate within the conservation community, particularly due to the huge practical and political obstacles to establishing or expanding protected areas on this scale. The new designation of "other effective area-based conservation measures" (OECMs) provides the opportunity for formal recognition of and support for areas delivering conservation outcomes outside the protected area estate. We argue that OECMs are essential to the achievement of big and bold conservation targets such as Half-Earth. But integration of OECMs into the conservation estate requires fundamental changes in protected area planning and how the conservation community deals with human rights and social safeguards issues; it therefore challenges our understanding of what constitutes "conservation". It will only succeed if the key drivers of biodiversity and ecosystem service loss are addressed in the whole planet. A broad, multifaceted and innovative approach, coupled with ambitious targets, provides our best hope yet of addressing complex conservation challenges. (C) 2018 Published by Elsevier B.V.Peer reviewe

    The Intersections of Biological Diversity and Cultural Diversity: Towards Integration

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    There is an emerging recognition that the diversity of life comprises both biological and cultural diversity. In the past, however, it has been common to make divisions between nature and culture, arising partly out of a desire to control nature. The range of interconnections between biological and cultural diversity are reflected in the growing variety of environmental sub-disciplines that have emerged. In this article, we present ideas from a number of these sub-disciplines. We investigate four bridges linking both types of diversity (beliefs and worldviews, livelihoods and practices, knowledge bases and languages, and norms and institutions), seek to determine the common drivers of loss that exist, and suggest a novel and integrative path forwards. We recommend that future policy responses should target both biological and cultural diversity in a combined approach to conservation. The degree to which biological diversity is linked to cultural diversity is only beginning to be understood. But it is precisely as our knowledge is advancing that these complex systems are under threat. While conserving nature alongside human cultures presents unique challenges, we suggest that any hope for saving biological diversity is predicated on a concomitant effort to appreciate and protect cultural diversity

    Embedding retrieval practice in undergraduate biochemistry teaching using PeerWise

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    Retrieval practice is an evidence‐based approach to teaching; here, we evaluate the use of PeerWise for embedding retrieval practice into summative assessment. PeerWise allows anonymous authoring, sharing, answering, rating, and feedback on peer‐authored multiple choice questions. PeerWise was embedded as a summative assessment in a large first‐year introductory biochemistry module. Engagement with five aspects of the tool was evaluated against student performance in coursework, exam, and overall module outcome. Results indicated a weak‐to‐moderate positive but significant correlation between engagement with PeerWise and assessment performance. Student feedback showed PeerWise had a polarizing effect; the majority recognized the benefits as a learning and revision tool, but a minority strongly disliked it, complaining of a lack of academic moderation and irrelevant questions unrelated to the module. PeerWise can be considered a helpful learning tool for some students and a means of embedding retrieval practice into summative assessment

    Adopting a flipped classroom approach for teaching molar calculations to biochemistry and genetics students

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    The flipped classroom is a relatively new active learning pedagogical intervention, gaining popularity as a blended learning methodology. The flipped classroom comprises two distinct parts, directed learning carried out at the student's own pace away from the classroom and an interactive, class-based activity encouraging problem-solving and experiential learning. This research presents a 1-year study to measure student performance and perception toward a flipped classroom approach to teaching core biochemical calculations to first-year undergraduate biochemistry and genetics students. A post-task questionnaire showed an overall positive student perception with an associated significant improvement in the end of module summative assessment. These results suggest that this teaching approach offers some advantages over more traditional teaching pedagogies
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