Teachers’ increasing use of cloud-based Geographical Information Systems (Web GIS) in an interactive way in Spanish secondary schools highlights the importance of researching the effectiveness of ...this new approach. This study employs action research qualitative methods, through direct teacher observation, and quantitative methods to analyze student grades following first use of Web GIS. Specifically, the research involved: a) Design: organizing a geopolitics’ lesson plan, with seven tasks, for a sample comprising 92 students at K10 level (15-16 years old); b) Comparison: contrasting the results of a traditional written exam following the use of two technologies (namely, Web GIS and a conventional PowerPoint presentation); c) Data collection: analyzing quantitative data via a descriptive and inference study of grades (involving a geopolitics exam; geography and history final term; Grade Point Average -GPA-; and the average grade of the entire term’s 10 curriculum subjects); d) Direct observation: assessing class interactions in which students are assisted with both technology (Web GIS or PowerPoint) and the clarification of concepts. The results demonstrate that Web GIS is a useful learning tool in geopolitics, with students getting better grades and no significant gender differences. Direct observation confirms how Web GIS technologies engage students; assist ‘ubiquitous learning’ from any place and at any time; improve their understanding of data analysis and spatial concepts; and enhanced digital competencies.
To develop a classifier for differentiating between healthy and early stage glaucoma eyes based on peripapillary retinal nerve fiber layer (RNFL) thicknesses measured with optical coherence ...tomography (OCT), using machine learning algorithms with a high interpretability.
Ninety patients with early glaucoma and 85 healthy eyes were included. Early glaucoma eyes showed a visual field (VF) defect with mean deviation >-6.00 dB and characteristic glaucomatous morphology. RNFL thickness in every quadrant, clock-hour and average thickness were used to feed machine learning algorithms. Cluster analysis was conducted to detect and exclude outliers. Tree gradient boosting algorithms were used to calculate the importance of parameters on the classifier and to check the relation between their values and its impact on the classifier. Parameters with the lowest importance were excluded and a weighted decision tree analysis was applied to obtain an interpretable classifier. Area under the ROC curve (AUC), accuracy and generalization ability of the model were estimated using cross validation techniques.
Average and 7 clock-hour RNFL thicknesses were the parameters with the highest importance. Correlation between parameter values and impact on classification displayed a stepped pattern for average thickness. Decision tree model revealed that average thickness lower than 82 µm was a high predictor for early glaucoma. Model scores had AUC of 0.953 (95%CI: 0.903-0998), with an accuracy of 89%.
Gradient boosting methods provide accurate and highly interpretable classifiers to discriminate between early glaucoma and healthy eyes. Average and 7-hour RNFL thicknesses have the best discriminant power.
The need is well recognized for additional data on endoluminal therapies for gastroesophageal reflux disease (GERD). This prospective multicenter clinical trial was designed to assess safety and ...effectiveness of Enteryx, a nonresorbable copolymer implanted into the lower esophagus, in reducing usage of proton pump inhibitors (PPIs) and improving reflux symptoms and quality of life.
Enteryx implantation was performed under fluoroscopic visualization without general anesthesia in 93 patients with symptomatic GERD responsive to and relapsing upon cessation of PPI therapy. Subjective and objective data were collected up to 12 months postprocedure. The criterion for treatment success was reduction in PPI dosage of > or =50%.
At 12 months, treatment success was attained in 86% (confidence interval, 77%-93%) of 74 evaluable patients and elimination of PPI therapy in 65% (confidence interval, 53%-76%). The treatment success rate by intent-to-treat analysis was 69% (confidence interval, 58%-78%). Reflux-related heartburn (P < 0.0001), regurgitation symptoms (P = 0.0005), and physical (P < 0.0001) and mental quality of life (P = 0.0012) scores improved. The most frequent complications were chest pain (77%), dysphagia/odynophagia (27%), and sensation of fever (26%).
Enteryx implantation provides an effective and safe alternative for management of gastroesophageal reflux, reducing medication dependency and symptoms and enhancing quality of life.
Molybdenum carbide has been prepared according to the carbothermal reduction method. Carbon black substrate was used as C-source whereas a H2-flow was the reducing agent. Two different H2 consumption ...steps were identified during the carburization treatment. The low temperature step is related to the reduction of Mo6+-to-Mo4+, the higher temperature process accounts for the deep reduction of Mo4+-to-metal Mo0 and its subsequent reaction with C to form the Mo-carbide. The influences of the maximum carburization temperature, carburization time, gas hourly space velocity regarding Mo-loading, heating rate and temperature of Ar pre-treatment were analyzed.
All these conditions are interrelated to each other. Thus, the carburization process ends at 700°C when Mo-loading is 10wt%, however Mo-loading higher than 10wt% requires higher temperatures. Carburization temperatures up to 800°C are needed to fulfill Mo-carbide formation with samples containing 50wt% Mo. Nevertheless, Ar pre-treatment at 550°C and slow heating rates favor the carburization, thus requiring lower carburization temperatures to reach the same carburization level.
H2-consumption profile (TPR) during the molybdenum carburization process, XRD patterns of the reduced Mo-samples after carburization and TEM-micrographs with two different enlargement of the samples with 5, 20 and 50wt% Mo. Display omitted
► Control of carburization variables: tailor the reduced/carbide Mo-phases (single/mixture). ► Mo carburization in two stages: (1) Mo6+–Mo4+; (2) Mo4+–Mo0 and, at once, MoC. ► The carburization process is faster than Mo4+ reduction. ► XPS probed: reduced Mo particles show core–shell structure. ► Core: reduced Mo (Mo2C, MoO2 and/or Mo0); Shell: 2–3nm of MoO3.
Sustainability has been evolving in tandem with societal progress, and as humankind advances, the vision and quality of sustainable development will also change, and most likely in ways that are as ...yet unpredictable. Sustainability might be incrementally achieved through the integration of economics with biology, philosophy, and neurology. It might also be realized by enhancing our knowledge, our sense and appreciation of environmental beauty and by qualitative and authentic improvements of places, especially tourism destinations. At the end, changes in the physical world only come through changes in human mentality and consciousness. In recent decades, the human mind has been producing exponential changes, though some of these have been delivered in perhaps less than desirable directions. Sustainability, in this sense, is an unending process of moving toward positive outcomes, defined by shifting human beliefs, desires, knowledge, and experiences. Health concerns have always prevented the desires and myths of traveling, but COVID 19 is also precluding the needs of moving.
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