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This study attempts to disclose the characteristics of knowledge integration in an interdisciplinary field by looking into the content aspect of knowledge.

There have been continued efforts in exploring how educational technology impacts human learning and performance. Through a synopsis of the trends and perspectives on educational technology in five countries by using the STEEP (social, technological, economic, environmental and political) framework, the authors discuss the direct influence of national policies on educational technology implementation and research, the constraints of the local STEEP elements of culture on the adoption of and research on innovation and change, and the strategies and reforms that different countries have adopted to prepare the next generation for the constantly changing, globalized twenty-first century. Limitations and future research following this work are discussed.

Li-rich Mn-based layered oxides with high specific capacity and operating voltages have become one of the most promising materials for lithium-ion batteries (LIBs). However, it still faces several issues of low initial Coulombic efficiency, poor electronic conductivity, and voltage fading due to oxygen release and transition metal rearrangement during cycling. In this study, Li1.2Mn0.54Ni0.13Co0.13O2 (LMR) cathode material with Na ion doping (LMNaR) and CeO2 nanoparticle surface modification (LMNaR@CeO2) is prepared to realize a synergistic modification effect. The doping of Na ions enlarges Li layer spacing to effectively promote the insertion and extraction of lithium ions, which makes the layered structure more stable to reduce the effect of the phase transition. And the CeO2 nanoparticle surface modification restrains the side reactions between electrode and electrolyte, stabilizes lattice oxygen, and eases oxygen release. As a result, LMNaR@CeO2 displays a specific capacity of 196 mAh g–1 after 100 cycles at 0.5 C with a capacity retention of 94% and a merely voltage decay of 0.16 V, which are much better than those of LMR with a specific capacity of 159.6 mAh g–1 and only a 79% capacity retention. Our strategy here provides a feasible approach for the development of Li-rich Mn-based cathode materials for long-lived LIBs. [ABSTRACT FROM AUTHOR]

HKUST-1 with high crystallinity has been successfully synthesized using a solvothermal method with Cu(NO3)2·3H2O as the copper source, 1,3,5-benzenetricarboxylic acid as the organic ligand, and N,N-dimethylformamide as the solvent. HKUST-1 exhibited a typical octahedral shape with a large number of micropores as well as possessed a high specific area and large porosity of 1488.03 cm2 g−1 and 0.774 cm3 g−1, respectively. The catalytic performance of HKUST-1 in the formaldehyde ethynylation reaction was evaluated in detail. The experimental results showed that HKUST-1 showed a good catalytic performance, achieving formaldehyde conversion, propargyl alcohol (PA) yield and 1,4-butynediol (BYD) yield of 95.1%, 60.2%, and 1.6%, respectively. The adsorption equilibrium constants KC of the products PA and BYD on HKUST-1 were calculated via adsorption calculation experiments to be 2.26 and 56.65, respectively, which theoretically verified that HKUST-1 is more favourable for the reaction to produce PA. The results of the reaction kinetics showed that the reaction of catalytic ethynylation of formaldehyde for selective propargyl alcohol production is first order for both formaldehyde and acetylene. [ABSTRACT FROM AUTHOR]

Designing efficient, inexpensive, and stable photocatalysts to degrade organic pollutants and antibiotics has become an effective way for environmental remediation. In this work, we successfully performed in situ growth of CdS QDs on the surface of elliptical BiVO4 to try to show the advantage of the binary heterojuncted photocatalyst (BVO@CdS) for the photocatalytic degradation of tetracycline (TC). The In situ growth of CdS QDs can provide a large number of reactive sites and also generate a larger contact area with BiVO4. In addition, compared with mechanical composite materials, in situ growth can significantly reduce the energy barrier at the interface between BiVO4 and CdS, providing more channels for the separation and migration of photogenerated charge carriers, and further improving reaction activity. As a result, BVO@CdS-0.05 shows the best degradation efficiency, with a degradation rate of 88% after 30 min under visible light. The TC photodegradation follows a pseudo-second-order reaction with a dynamic constant of 0.472 min−1, which is 6.47 times that of pure BiVO4, 7.24 times that of pure CdS QDs and 2 times that of the mechanical composite. The degradation rate of BVO@CdS-0.05 decreases to 77.8% with a retention rate of 88.5% after four cycles, demonstrating excellent stability. Through liquid chromatography-mass spectrometry (LC-MS) analysis, two possible pathways for TC degradation are proposed. Through free radical capture experiments, electron spin resonance measurements, and photoelectrochemical comprehensive analysis, it is confirmed that BVO@CdS composites have constructed an efficient Z-scheme heterojunction via in situ growth, thereby highly enhancing the separation and transport efficiency of charge carriers. [ABSTRACT FROM AUTHOR]

Interplay between the outer steel tubes and the core concrete provides an important guarantee for the superior performance of concrete-filled steel tube (CFST) columns compared to that of reinforced concrete columns. In order to optimize the construction of the large-size non-studded CFST columns in an on-going practical project, the strain distributions in the column under construction were measured and tracked, and the law of the strain distributions of the column under construction is revealed. The study finds that the plane section assumption was not applicable to the strain distributions of the column. Nonlinear variations in the strain levels were observed under bi-directional bending of the column. The absence of studs inside the steel tube significantly weakened the interplay of the outer steel tube and the core concrete by means of a significant slip between the concrete and the steel tube at the column corners. The concrete and the steel tube tended to be stressed and deformed independently. Practical suggestions are given for the design and construction of this type of column. The study results are expected to lay a basic and valuable foundation for in-depth investigations on the mechanical behavior of large-size non-studded concrete-filled steel tube columns under construction. [ABSTRACT FROM AUTHOR]

The regularization method has a direct impact on the accuracy of the reconstructed sound field in the process of inverse calculation of near−field acoustic holography using the equivalent source method. To expand the frequency range of sound field reconstruction and improve computational accuracy, a forward-backward splitting equivalent source method based on s−difference was proposed, which uses the ratio of the output results of the broadband acoustic holography algorithm as the regularization parameter. Numerical simulations of single source and coherent source sound fields were conducted under different frequency conditions to analyze the performance of the forward-backward splitting regularization algorithm based on s−difference, and experimental verification was performed. The simulation results show that the proposed method can accurately reconstruct the sound field in a wider frequency range, and has high accuracy in reconstructing the sound field of low−frequency coherent sources. The experimental results demonstrate the accuracy and effectiveness of this method in reconstructing mid−to−low−frequency sound fields. [ABSTRACT FROM AUTHOR]

We have evaluated the effects of Shufeng Tongqiao decoction on the efficacy of tobramycin drops and levofloxacin drops in treating acute suppurative otitis media. To this end, 200 patients with acute suppurative otitis media were divided into 4 treatment groups (A, B, C, and D) of 50 patients per group. Patients in groups A and B received a combination of Shufeng Tongqiao decoction plus levofloxacinor and tobramycin drops, respectively. Patients in groups C and D received only levofloxacinor and tobramycin drops, respectively. Among these four groups, group B (Shufeng Tongqiao decoction + tobramycin) was the most effective in decreasing the time of tinnitus and ear pain, discharge of pus and hearing loss (P < 0.05), and serum levels of proinflammatory cytokines. Also, this group promoted the quality of life as well as the clearance rate of pathogenic bacteria much faster relative to other groups. In conclusion, Shufeng Tongqiao decoction in combination with tobramycin drops has a significant curative effect in treating acute suppurative otitis media, which can improve the clearance rate of pathogenic bacteria, shorten the recovery time of patients, and promote the quality of life of patients. [ABSTRACT FROM AUTHOR]

Objective: To compare the therapeutic effects of two types of tympanostomy tube, in terms of extrusion time and recurrence rate, after endoscopic ventilation tube placement in adults with otitis media with effusion. Materials and methods: The clinical data for 125 ears from 91 patients who underwent endoscopic ventilation tube placement was retrospectively reviewed. The ears included in the study were divided into groups A and B. The Shepard tube was used in all ears from group A. The T-tube was used in all ears from group B. Extrusion time and recurrence rate were recorded and statistically analyzed. Results: Group A included 103 ears (82.4%). Group B included 22 ears (17.6%). The average extrusion time for group A was significantly shorter than that for group B (160.5 ± 106.6 days vs 274.1 ± 120.5 days, p