38 research outputs found
The sustainable approach to the green space layout in highdensity urban environment: a case study of Macau peninsula
AbstractBased on a case study of Macau peninsula, this paper explores a sound approach to the urban green space development in high-density urban environment that could enhance the sustainability of the city
DiffSeer: Difference-based Dynamic Weighted Graph Visualization
Existing dynamic weighted graph visualization approaches rely on users'
mental comparison to perceive temporal evolution of dynamic weighted graphs,
hindering users from effectively analyzing changes across multiple timeslices.
We propose DiffSeer, a novel approach for dynamic weighted graph visualization
by explicitly visualizing the differences of graph structures (e.g., edge
weight differences) between adjacent timeslices. Specifically, we present a
novel nested matrix design that overviews the graph structure differences over
a time period as well as shows graph structure details in the timeslices of
user interest. By collectively considering the overall temporal evolution and
structure details in each timeslice, an optimization-based node reordering
strategy is developed to group nodes with similar evolution patterns and
highlight interesting graph structure details in each timeslice. We conducted
two case studies on real-world graph datasets and in-depth interviews with 12
target users to evaluate DiffSeer. The results demonstrate its effectiveness in
visualizing dynamic weighted graphs
Robust estimation of bacterial cell count from optical density
Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data
Load–Temperature Coupling Effect on the Base Plate End of the Whole Tram Road
Although trams have been widely recognized, systematic and comprehensive research on their design and construction is lacking. Based on the ABAQUS finite element software, we constructed a three-dimensional finite element analysis model of the overall track bed of the tram. Taking the most unfavorable working condition of load and temperature coupling as the research object, that is from 5:30 to 6:00 a.m., the load was applied to the plate end position. The simulation experiments were carried out by selecting different thicknesses of the track bed slab, support layer thickness, contact conditions between the track bed slab and the support layer, the modulus of the track bed slab, the modulus of the support layer and the soil foundation strength, and the stress and deflection of the subgrade were calculated. The most unfavorable load–temperature coupling condition was taken as the research object, that is, applying a load of 5.5–6 points on the plate end. Different track bed slab thicknesses, support layer thicknesses, contact conditions between track bed slab and support layer, track bed slab moduli, support layer moduli, and foundation strengths were utilized to conduct simulation tests for calculating the stress and deflection of the subgrade. Under the coupling effect of load on the end of the slab and the effect of temperature, changing the thickness of the track bed slab and the coefficient of friction between layers can improve the lateral force and deflection of the track bed slab. The effect of deflection is small. Changing the thickness of the support layer has an insignificant effect on the stress on the top surface of the soil foundation and the deflection of the top surface of the subgrade. The modulus of the track bed slab can affect the lateral force and deflection of the track bed slab, but it only slightly affects the longitudinal force and deflection of the track bed slab and the longitudinal and lateral force and deflection of the soil foundation. The modulus of the supporting layer only slightly affects the vertical and horizontal force and deflection of the track bed slab and soil foundation. The soil foundation modulus has the greatest influence on the vertical and horizontal forces and deflection of the track bed slab and soil foundation
Load–Temperature Coupling Effect on the Base Plate End of the Whole Tram Road
Although trams have been widely recognized, systematic and comprehensive research on their design and construction is lacking. Based on the ABAQUS finite element software, we constructed a three-dimensional finite element analysis model of the overall track bed of the tram. Taking the most unfavorable working condition of load and temperature coupling as the research object, that is from 5:30 to 6:00 a.m., the load was applied to the plate end position. The simulation experiments were carried out by selecting different thicknesses of the track bed slab, support layer thickness, contact conditions between the track bed slab and the support layer, the modulus of the track bed slab, the modulus of the support layer and the soil foundation strength, and the stress and deflection of the subgrade were calculated. The most unfavorable load–temperature coupling condition was taken as the research object, that is, applying a load of 5.5–6 points on the plate end. Different track bed slab thicknesses, support layer thicknesses, contact conditions between track bed slab and support layer, track bed slab moduli, support layer moduli, and foundation strengths were utilized to conduct simulation tests for calculating the stress and deflection of the subgrade. Under the coupling effect of load on the end of the slab and the effect of temperature, changing the thickness of the track bed slab and the coefficient of friction between layers can improve the lateral force and deflection of the track bed slab. The effect of deflection is small. Changing the thickness of the support layer has an insignificant effect on the stress on the top surface of the soil foundation and the deflection of the top surface of the subgrade. The modulus of the track bed slab can affect the lateral force and deflection of the track bed slab, but it only slightly affects the longitudinal force and deflection of the track bed slab and the longitudinal and lateral force and deflection of the soil foundation. The modulus of the supporting layer only slightly affects the vertical and horizontal force and deflection of the track bed slab and soil foundation. The soil foundation modulus has the greatest influence on the vertical and horizontal forces and deflection of the track bed slab and soil foundation
Inflammatory Mediators in Induced Sputum and Airway Hyperresponsiveness in Cough Variant Asthma during Long-Term Inhaled Corticosteroid Treatment
Objective. This study aimed to investigate improvements in inflammatory mediator levels in induced sputum and airway hyperresponsiveness (AHR) in cough variant asthma (CVA) during long-term inhaled corticosteroid (ICS) treatment. Patients and Methods. Patients with CVA (=35) and classic asthma (=26) and healthy subjects (=24) were recruited into this study. All patients were treated with budesonide (400 μg/day). Measurement of inflammatory mediators in induced sputum and PD20-FEV1 (the accumulated provocative dose resulting in a 20% decrease in FEV1) in histamine-challenged subjects was performed every three months after the start of medication. Interleukin- (IL-) 5 and IL-10 were assayed by ELISA, and the percentage of eosinophils was detected with Giemsa stain. Trends during the follow-up period were analyzed using a general linear model. Results. Inflammatory mediator levels in induced sputum and PD20-FEV1 in patients with CVA and classic asthma differed from those in the control group, although no differences were found in the two asthmatic groups. PD20-FEV1 significantly increased in CVA patients after ICS treatment for 3 months, while classic asthma patients exhibited a delayed change in AHR. After ICS treatment, levels of IL-5 and IL-10 as well as the percentage of eosinophils in the CVA group were altered at 3 months and 6 months, respectively. Accordingly, the level of inflammatory mediators in classic asthma changed more slowly. Conclusion. CVA has a greater improvement in airway inflammation and airway hyperresponsiveness (AHR) than classic asthma with respect to inhaled corticosteroid (ICS). Short-term ICS considerably reduces AHR although longer treatment is required for complete control of airway inflammation
Retrieval of Nitrogen Content in Apple Canopy Based on Unmanned Aerial Vehicle Hyperspectral Images Using a Modified Correlation Coefficient Method
The accurate retrieval of nitrogen content based on Unmanned Aerial Vehicle (UAV) hyperspectral images is limited due to uncertainties in determining the locations of nitrogen-sensitive wavelengths. This study developed a Modified Correlation Coefficient Method (MCCM) to select wavelengths sensitive to nitrogen content. The Normalized Difference Canopy Shadow Index (NDCSI) was applied to remove the shadows from UAV hyperspectral images, thus yielding the canopy spectral information. The MCCM was then used to screen the bands sensitive to nitrogen content and to construct spectral characteristic parameters. Finally, the optimal model for nitrogen content retrieval was established and selected. As a result, the screened sensitive wavelengths for nitrogen content selected were 470, 474, 490, 514, 582, 634, and 682 nm, respectively. Among the nitrogen content retrieval models, the best model was the Support Vector Machine (SVM) model. In the training set, this model outperformed the other models with an R2 of 0.733, RMSE of 6.00%, an nRMSE of 12.76%, and a MAE of 4.49%. Validated by the ground-measured nitrogen content, this model yielded good performance with an R2 of 0.671, an RMSE of 4.73%, an nRMSE of 14.83%, and a MAE of 3.98%. This study can provide a new method for vegetation nutrient content retrieval based on UAV hyperspectral data
Retrieval of Nitrogen Content in Apple Canopy Based on Unmanned Aerial Vehicle Hyperspectral Images Using a Modified Correlation Coefficient Method
The accurate retrieval of nitrogen content based on Unmanned Aerial Vehicle (UAV) hyperspectral images is limited due to uncertainties in determining the locations of nitrogen-sensitive wavelengths. This study developed a Modified Correlation Coefficient Method (MCCM) to select wavelengths sensitive to nitrogen content. The Normalized Difference Canopy Shadow Index (NDCSI) was applied to remove the shadows from UAV hyperspectral images, thus yielding the canopy spectral information. The MCCM was then used to screen the bands sensitive to nitrogen content and to construct spectral characteristic parameters. Finally, the optimal model for nitrogen content retrieval was established and selected. As a result, the screened sensitive wavelengths for nitrogen content selected were 470, 474, 490, 514, 582, 634, and 682 nm, respectively. Among the nitrogen content retrieval models, the best model was the Support Vector Machine (SVM) model. In the training set, this model outperformed the other models with an R2 of 0.733, RMSE of 6.00%, an nRMSE of 12.76%, and a MAE of 4.49%. Validated by the ground-measured nitrogen content, this model yielded good performance with an R2 of 0.671, an RMSE of 4.73%, an nRMSE of 14.83%, and a MAE of 3.98%. This study can provide a new method for vegetation nutrient content retrieval based on UAV hyperspectral data
Implementation of the Flipped Classroom Combined with Problem-Based Learning in a Medical Nursing Course: A Quasi-Experimental Design
Background: Medical Nursing is one of the most important core courses in nursing education, and the emergence of the flipped classroom has made up for the shortcomings of traditional teaching and improved the effectiveness of teaching. However, it is worth exploring how to maximize the effect of students’ self-study before class while making full use of classroom teaching to promote the cultivation of students’ abilities, so that the flipped classroom can have a maximal teaching effect. Therefore, this study explored the effect of a flipped-classroom teaching mode based on a small private online course (SPOC) combined with problem-based learning (PBL) in a course of Medical Nursing. Methods: Nursing undergraduates from the years 2018 (control group) and 2019 (experimental group), respectively, used the traditional lecture method and the flipped-classroom teaching mode based on a SPOC combined with PBL. The teaching effect was evaluated by teaching-mode-recognition evaluation, critical thinking measurement, and academic achievement. Results: The scores of teaching-mode recognition evaluated by the students in the experimental group were higher than those in the control group in the following five aspects: “helping to improve learning interest” (p = 0.003), “helping to improve autonomous learning ability” (p = 0.002), “helping to improve communication and cooperation ability” (p p = 0.012), and “helping to promote self-perfection and sense of achievement” (p = 0.001). Compared with the control group, the score on the “analytical ability” dimension of the Critical Thinking Disposition Inventory in the experimental group was higher (p = 0.030). The excellent rates of the final theoretical examination (p = 0.046) and comprehensive case analysis (p = 0.046) in the experimental group were higher than those in the control group. Conclusions: The flipped-classroom teaching mode based on a SPOC combined with PBL can promote students’ abilities of autonomous learning, communication and cooperation, and clinical and critical thinking; improves their academic performance; and is recognized and welcomed by them. However, to extend the flipped-classroom teaching model of a SPOC combined with PBL to other nursing education courses, more optimization and evaluation are required