169 research outputs found
Can Educational Robots Improve Student Creativity: A Meta-analysis based on 48 Experimental and Quasi-experimental Studies
Cultivating innovative talents has become a critical strategy for building China into a strong country in science and technology. Catering to the trend of educational reform in the intelligent era, the use of robotics in developing student creativity proves to be of greater practical value. The findings of this study are that: first, the overall effect of educational robotics on student creativity reaches above-moderate level; second, educational robotics has more significant effects on creativity of primary and junior secondary students; third, in terms of subjects, robotics courses can most effectively promote student creativity; fourth, among various teaching topics, prototype creation has the most substantial impact on student creativity; fifth, in terms of instruction methods, inquiry-driven teaching can best stimulate student creativity; sixth, compared with ordinary classrooms, the laboratory environment is more favorable for the development of student creativity. The paper also offers recommendations for popularizing robotics curriculum at different education levels
Coupling system of silver carbonate nanoparticles and bismuth oxyiodide nanosheets with enhanced photocatalytic properties
274-284In this work, silver carbonate nanoparticles and BiOI nanosheets have been prepared separately and binary Ag2CO3/BiOI composite are synthesized via a facile solvo thermal method. The as-prepared materials have been well characterized using techniques covering X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), High-resolution transmission electron microscopy (HRTEM), ultraviolet-visible (UV-vis) diffuse reflectance spectroscopy, X-ray photoelectron spectroscopy (XPS), Photoluminescence (PL) emission spectroscopy. The photocatalytic activity of the as-synthesized materials has been evaluated for degrading various model pollutants (methyl orange, phenol and p-nitroaniline). It has been found that the incorporation of co-catalyst BiOI could promote the catalytic activity of Ag2CO3 and suppress the serious photocorrosion of Ag2CO3. Thus the Ag2CO3/BiOI composite showed excellent catalytic recycling stability. Moreover, the underlying mechanism has been investigated through radical trapping experiments. The results demonstrate that photoinduced holes are the main active species. The improvement in activity of Ag2CO3/BiOI could be attributed to the charge transfer between the heterojunction. Also, its good stability and reusability establish its promising potential for catalytic applications
Muscle tuning and preferred movement path: do we need a paradigm shift or should we redefine the old? – comment on Nigg et al.
In the feature paper “Muscle tuning and preferred movement path – a paradigm shift“, Benno Nigg and colleagues discuss that the impact and pronation paradigm should be abandoned as there is not enough biomechanical and epidemiological evidence supporting these paradigms. We agree that the paradigms, as defined in the paper, are currently not supported by strong scientific evidence however we argue that the lack of evidence originates from shortcomings in the methodological approach to these paradigms. In our commentary, we argue for a redefinition of the paradigms rather than defining two ‘new’ paradigms. A better methodological approach and definitions of the paradigms based on the current evidence are needed rather than to abandon them
Seasonal behaviour of tidal damping and residual water level slope in the Yangtze River estuary: identifying the critical position and river discharge for maximum tidal damping
As a tide propagates into the estuary, river discharge affects tidal damping, primarily via a friction term,
attenuating tidal motion by increasing the quadratic velocity in the numerator, while reducing the effective friction
by increasing the water depth in the denominator. For the
first time, we demonstrate a third effect of river discharge
that may lead to the weakening of the channel convergence
(i.e. landward reduction of channel width and/or depth). In
this study, monthly averaged tidal water levels (2003–2014)
at six gauging stations along the Yangtze River estuary are
used to understand the seasonal behaviour of tidal damping and residual water level slope. Observations show that
there is a critical value of river discharge, beyond which
the tidal damping is reduced with increasing river discharge.
This phenomenon is clearly observed in the upstream part
of the Yangtze River estuary (between the Maanshan and
Wuhu reaches), which suggests an important cumulative effect of residual water level on tide–river dynamics. To understand the underlying mechanism, an analytical model has
been used to quantify the seasonal behaviour of tide–river
dynamics and the corresponding residual water level slope
under various external forcing conditions. It is shown that a
critical position along the estuary.info:eu-repo/semantics/publishedVersio
Facile synthesis of chitosan-capped ZnS quantum dots as an eco-friendly fluorescence sensor for rapid determination of bisphenol A in water and plastic samples
This paper describes a novel eco-friendly fluorescence sensor for determination of bisphenol A (BPA) based on chitosan-capped ZnS quantum dots (QDs). By using safe and inexpensive materials, nontoxic ZnS QDs were synthesized via an environment-friendly method using chitosan as a capping agent. The as-prepared ZnS QDs exhibited characteristic absorption (absorbance edge at 310 nm) and emission (maxima at 430 nm) spectra with a relatively high fluorescence quantum yield of 11.8%. Quantitative detection of BPA was developed based on fluorescence quenching of chitosan-capped ZnS QDs with high sensitivity and selectivity. Under optimal conditions, the fluorescence response of ZnS QDs was linearly proportional to BPA concentration over a wide range from 0.50 to 300 mu g L-1 with a detection limit of 0.08 mu g L-1. Most of the potentially coexisting substances did not interfere with the BPA-induced quenching effect. The proposed analytical method for BPA was successfully applied to water and plastic real samples. The possible quenching mechanism is also discussed
Graphene-Paper Based Electrochemical Sensors
Graphene paper as a new form of graphene-supported nanomaterials has received worldwide attention since its first report in 2007. Due to their high flexibility, lightweight and good electrical conductivity, graphene papers have demonstrated the promising potential for crucial applications in electrochemical sensors and energy technologies among others. In this chapter, we present some examples to overview recent advances in the research and development of two-dimensional (2D) graphene papers as new materials for electrochemical sensors. The chapter covers the design, fabrication, functionalization and application evaluations of graphene papers. We first summarize the mainstream methods for fabrication of graphene papers/membranes, with the focus on chemical vapour deposition techniques and solution-processing assembly approaches. A large portion of this chapter is then devoted to the highlights of specific functionalization of graphene papers with polymer and nanoscale functional building blocks for electrochemical-sensing purposes. In terms of electrochemical-sensing applications, the emphasis is on enzyme-graphene and nanoparticle-graphene paper-based systems for the detection of glucose. We finally conclude this chapter with brief remarks and outlook
THE INFLUENCE OF HEEL HEIGHT ON ANKLE KINEMATICS DURING STANDING, WALKING, JOGGING AND SIDESTEPPING IN CHILDREN
The aim of this study was to quantify the effects of heel-forefoot height on ankle kinematics during locomotion in children. Measurements were taken by a motion capture system and a force plate on five children. They were asked to perform standing, walking, jogging and sidestepping in barefoot, low heel, standard heel and high heel shoe conditions. Results showed that rearfoot plantarflexion angle was different from shoe rake during standing. There was more ankle plantarflexion as heel height increased during walking, jogging and sidestepping. Ankle inversion velocity increased with shod condition but not significantly. High heel height will affect ankle kinematics during locomotion, which may increase the risk of foot problems. Children and their parents should choose footwear with caution
Triolein-based polycation lipid nanocarrier for efficient gene delivery: characteristics and mechanism
We proposed to develop a polycation lipid nanocarrier (PLN) with higher transfection efficiency than our previously described polycation nanostrucutred lipid nanocarrier (PNLC). PLN was composed of triolein, cetylated low-molecular-weight polyethylenimine, and dioleoyl phosphatidylethanolamine. The physicochemical properties of PLN and the PLN/DNA complexes (PDC) were characterized. The in vitro transfection was performed in human lung adenocarcinoma (SPC-A1) cells, and the intracellular mechanism was investigated as well. The measurements indicated that PLN and PDC are homogenous nanometer-sized particles with a positive charge. The transfection efficiency of PDC significantly increased with the content of triolein and was higher than that of PNLC and commercial Lipofectamine™ 2000. In particular, the transfection of PLN in the presence of 10% serum was more effective than that in its absence. With the help of specific inhibitors of chlorpromazine and filipin, the clathrin-dependent endocytosis pathway was determined to be the main contributor to the successful transfection mediated by PLN in SPC-A1 cells. The captured images verified that the fluorescent PDC was localized in the lysosomes and nuclei after endocytosis. Thus, PLN represents a novel efficient nonviral gene delivery vector
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