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The purpose of this study was to explore instructional designs for promoting inquiry practices in secondary school textbooks. Three criteria were employed to select the textbooks: (1) approved by the Ministry of Education in Singapore and the Ministry of Education and Culture in Indonesia, (2) used in secondary schools, and (3) included content and practices based on the current curriculum. Based on these criteria, six science textbooks from Singapore and three from Indonesia were selected for further coding in the dimensions of learning goals of inquiry skills, nature of scientific inquiry, and inquiry types. The results showed that more activities in both the Singaporean and Indonesian textbooks focus on observing and interpreting skills. However, few activities in the textbooks from either country provide an opportunity for students to engage nature of scientific inquiry. In addition, more activities in the Singaporean textbooks were designed as guided inquiry than those in the Indonesian textbooks. Finally, it is suggested that inquiry activities in textbooks should be revised to include nature of scientific inquiry, and more textbook analysis studies are needed to reveal characteristics of inquiry activities in textbooks for different subjects. [ABSTRACT FROM AUTHOR]

The purpose of this study is to analyze the learning goals, nature of science, inquiry skills, understanding of inquiry, and inquiry types in the senior high school physics textbooks in Indonesia. We selected the textbooks based on three criteria: (1) approved by the Ministry of Education and Culture in Indonesia, (2) widely used in senior high schools, and (3) included content and practices based on the current curriculum. Content analysis was used to analyze 10th, 11th, and 12th grade textbooks. We found that more physics topics focused on the cognitive than on the epistemic, affective, and sociocultural aspects in these textbooks. The findings show that nature of science was emphasized in the textbooks, but they were more focused on science as a cognitive-epistemic system. Furthermore, we found that structured inquiry was more emphasized than confirmed and guided inquiry. Finally, structured inquiry focused more on inquiry skills than on the understanding of inquiry in all three textbooks, while observing and communicating skills were more emphasized in the physics activities. It is suggested that more studies need to develop inquiry activities that focus on understanding inquiry. [ABSTRACT FROM AUTHOR]

The present study aimed at developing chitosan/collagen protease-based composite membranes loaded with enzyme nanoparticles and accessing its efficient biodegradation using a recombinantly produced aspartic protease from Aspergillus fumigatus (AfAP) with functional biochemical properties. By using Fourier transform infrared spectroscopy (FT-IR), X-ray diffractometry (XRD), and scanning electron microscopy (SEM) to analyze the resulting membranes, it was found that the ENPs and the chitosan-collagen composite membranes were highly compatible. Thermal properties (TG, DTG and DSC) were employed to evaluate the changes in the structural and physical properties which reached 384.94 °C, and a residual mass of 4.21 ± 0.13%. The ENPs loaded membranes exhibited marginally improved antioxidant and microbial growth inhibitory activities reaching 57.29 ± 2.77% and 10.33 ± 0.65 mm respectively. Additionally, the respective protease employed for the degradation studies was successfully expressed in Pichia pastoris (GS115) host cells, with functional pH and temperature optima between pH 4.0–5.0 and 60 °C respectively, and specific activity of 8408.9 ± 305.6 U/mg. It also exhibited enhanced specificity to its substrates upon collagen, chitosan, Bovine serum albumin (BSA), casein and casein sodium salt degradation with specific activities of 1477 ± 99.1, 1177 ± 103, and 1051.6 ± 60.7 U/mg respectively. Furthermore, the composite membranes showed excellent biodegradability by the 6th day in a natural environment treated with the aspartic protease from Aspergillus fumigatus (AfAP). Thus, the developed nanocomposite membranes from chitosan/collagen exhibited great potential and can well mimic the functions of a new generation of biodegradable and sustainable membranes. [ABSTRACT FROM AUTHOR]

The main work of this paper is to study the soliton solutions and asymptotic behavior of the integrable reverse space-time nonlocal Sasa–Satsuma equation, which is derived from the coupled two-component Sasa–Satsuma system with a specific constraint. The soliton solutions of the nonlocal Sasa–Satsuma equation are constructed through solving the inverse scattering problems by Riemann–Hilbert method. Compared with local systems, discrete eigenvalues and eigenvectors of the reverse space-time nonlocal Sasa–Satsuma equation have novel symmetries and constraints. On the basis of these symmetry relations of eigenvalues and eigenvectors, the one-soliton and two-soliton solutions are obtained and the dynamic properties of these solitons are shown graphically. Furthermore, the asymptotic behaviors of two-soliton solutions are analyzed. All these results about physical features and mathematical properties may be helpful to comprehend nonlocal nonlinear system better. [ABSTRACT FROM AUTHOR]

In order to cultivate students to be able to participate in public affairs and make decisions about socioscientific issues (SSI), a web-based module was designed for students to collaboratively engage in the decision-making (DM) process. This study attempted to identify students' discourse characteristics that might lead to formulating an evidence-based decision on SSI. Twenty-nine Grade 10 students were randomly divided into eight groups of three or four. The transcribed data of one case from each performance level were compared to investigate the interplay between groups' DM performances and discourse characteristics. The results showed that the group that gained a high score on the DM group worksheet engaged in the metacognitive discussion for planning procedures of the module tools and in the conceptual exchanges to accomplish the tasks. The members of this group could initiate and extend ideas, provide prompts, and confirm or reject each other's ideas, resulting in sustained interactive dialogs that allowed them to learn from one another. This indicated that students need to be encouraged to clarify the task goals, plan procedures, monitor their performance, and exchange their ideas actively. The implications of how collaborative discourse promote students' SSI DM performance, and the better design and enactment of SSI modules are discussed. [ABSTRACT FROM AUTHOR]

This paper studies reverse space and/or time nonlocal Fokas–Lenells (FL) equation, which describes the propagation of nonlinear light pulses in monomode optical fibers when certain higher-order nonlinear effects are considered, by Hirota bilinear method. Firstly, we construct variable transformations from reverse space nonlocal FL equation to reverse time and reverse space-time nonlocal FL equations. Secondly, the multisoliton and quasi-periodic solutions of the reverse space nonlocal FL equation are derived through Hirota bilinear method, and the soliton solutions of reverse time and reverse space-time nonlocal FL equations are given through variable transformations. Also, dynamical behaviors of the multisoliton solutions are discussed in detail by analyzing their wave structures. Thirdly, asymptotic analysis of two- and three-soliton solutions of reverse space nonlocal FL equation is used to investigate the elastic interaction and inelastic interaction. Finally, the infinite conservation laws of three types of nonlocal FL equations are found by using their lax pairs. The results obtained in this paper possess new properties that different from the ones for FL equation, which are useful in exploring novel physical phenomena of nonlocal systems in nonlinear media. [ABSTRACT FROM AUTHOR]

In the present study, we aimed to investigate the effects of puerarin on the hyperpermeability of vascular endothelial cells induced by lipopolysaccharide (LPS) and its underlying mechanisms. Human umbilical vein endothelial cells (HUVECs) were pre-incubated with puerarin (25, 50, and 100 μM) for 1 h, and then exposed to LPS (1 μg/mL). The monolayer permeability of endothelial cells was assessed by measuring the paracellular flux of FITC-dextran 40,000 (FD40). The expression of vascular endothelial cadherin (VE-cadherin) in HUVECs was examined by Western blotting analysis. A total of 18 mice were randomly assigned into three groups as follows: control group, LPS group, and puerarin group. The pulmonary W/D ratio (wet-to-dry weight ratios) was calculated, and the lung morphology was examined. The levels of TNF-α and IL-1β in cell supernatant and mouse serum were determined by ELISA. Compared with the control group, LPS obviously increased the flux of FD40 and the monolayer permeability, raised the levels of TNF-α and IL-1β in cell supernatant, and reduced the VE-cadherin expression in HUVECs. However, puerarin (25, 50, and 100 μM) was able to relieve such LPS-induced increase in flux of FD40 and then reduce the hyperpermeability. Puerarin decreased the levels of TNF-α and IL-1β in cell supernatant and increased the VE-cadherin expression in HUVECs (P < 0.05). Moreover, LPS obviously increased the levels of TNF-α and IL-1β in mouse serum and elevated the pulmonary W/D ratios, resulting in lung injury. However, all of above-mentioned LPS-induced changes were improved by puerarin pre-treatment. Puerarin could alleviate LPS-induced hyperpermeability in endothelial cells via preventing downregulation of endothelial cadherin. [ABSTRACT FROM AUTHOR]

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Overtaking accidents caused by improper operations performed by a driver occur frequently. However, most studies on overtaking safety have neglected research into driver control input. A novel method is proposed to obtain the driver control input during the overtaking process. Meanwhile, to improve the safety of overtaking, two types of safe distances, and the time of the overtaking are considered. Path constraints are established when considering the two types of safe distances. An optimal control model is established to solve the minimum time maneuver under multiple constraints. Using the Gauss pseudospectral method, the optimal control problem is converted into a nonlinear programming problem, which is then solved through sequential quadratic programming (SQP). In addition, the effectiveness of the proposed method is verified based on the results of a Carsim simulation. The simulation results show that by adopting an inverse dynamics method to solve the manipulation problem of the vehicle's minimum overtaking time, the manipulation capability of a vehicle in completing an overtaking safely within the minimum time can be obtained. This method can provide a reference for research into the active safety of manned and unmanned vehicles. [ABSTRACT FROM AUTHOR]