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The interest in Computational Thinking (CT) development among young learners increases with the number of studies located in literature. In this study, a meta-analysis was conducted to address two main objectives: (a) the effectiveness of empirical interventions on the development of CT in children aged of 3-8 years; and (b) the variables that influence the effectiveness of the interventions. Following PRISMA procedures, we identified 17 empirical studies with 34 effect sizes and 1665 participants meeting the inclusion criteria from Web of Science database. Overall, we found a statistically significant large effect size (d = 0.83 [95% CI: 730, 0.890]; p < 0.001) on the CT development of 3-8 years old children, which provides empirical support for having young children to engage in CT experiences. The effect size was significantly influenced by moderating variables including gender, scaffolding, and education level. Intervention length showed a marginally significant effect. Therefore, educators could refer to the significant moderators when designing tailored interventions for CT development in early childhood education while a call for more empirical studies of CT development in young children is proposed.

Mobile-assisted Language Learning (MALL) has been widely adopted in teaching and learning, yet there has been scant research concerning speaking test adaptation. An emerging type of mobile application is designed to facilitate test takers' performance in a high-stakes speaking test (e.g., the International English Language Testing System (IELTS)). Such an exam-oriented mobile application provides customized learning opportunity with automatic feedbacks through artificial intelligence (AI) technology for users to enhance their speaking skills. This study aims to explore the attitudes of test takers on using exam-oriented mobile application to adapt in testing environment as influenced by their perceptions through the theory of Technology Acceptance Model. 235 Chinese IELTS test takers with experience of using such applications were invited to fill out an online questionnaire. Collected data were analysed through statistical method, textual analysis, word cloud approach, and sentiment analysis. Results revealed that test takers' perceived usefulness and perceived ease of use towards the exam-oriented mobile application explained their attitudes to use such an application. They also expressed the concern of personalized AI function to support speaking test adaptation. Implications for educators, test taker, and application developers are provided.

Students' beliefs and attitudes have a direct impact on their behavior and engagement in the learning of mathematics. This study examined students' beliefs of dynamic mathematics lessons through the lens of the contemporary theory of metaphor. Participants of the study were grade 10 students in a Macao private secondary school. 51 students attended dynamic inquiry-based lessons and used dynamic geometry software. After the lessons, students' attitudes of the dynamic lessons were uncovered using open-ended questions and a Likert-item questionnaire. Students held a polarized view regarding the dynamic mathematics lessons claiming they were rewarding but challenging. In order to develop students' positive attitudes towards the dynamic mathematics lessons, teachers should plan more diversified pedagogy to meet the different learning approaches of students.

The pervasive use of the Internet and technology has its impact on citizens' civic participation. There are growing numbers of research which explore digital citizenship (DC) for citizens' better civic participation in the information society. With the growing attention of digital citizenship, a systematic review of empirical research focused on digital citizenship in the past decade (2010-2020) was conducted to serve the need of different stakeholders. Synthesis was based on research purposes, methods, population, geographic distribution, instruments and factors that affect digital citizenship. Results showed that the research of the DC empirical studies varied. The themes of DC practice, education and factors attracted attention. A few reliable and valid instruments have been developed to measure digital citizenship targeted for different populations. Demographic factors, Internet use factors, psychological factors and social factors of an individual predict one's digital citizenship. These factors may serve as indicators for policy makers to draft DC policy and educators to plan for the DC program in the society. Suggestions are provided for practitioners based on the findings.

In current engineering, the transition process of pump turbines from pump to turbine mode mainly includes the shutdown process of pump operating and the startup process of turbine operating, and the switching of working conditions mostly depends on the opening and closing of the ball valve. While, this article focuses on the transitional process of pump turbine from pump to turbine condition without relying on ball valve, which will significantly reduce the response time of the unit and enable quick switching of operating conditions in emergency situations. In this study, the torque balance equation is employed to analyze the transition process of the entire flow system from pump to turbine operation. Additionally, the entropy production theory is utilized to investigate the correlation between pressure, flow state, and energy loss in the pump-turbine, shedding light on the changes in external characteristics through the evolution of internal characteristics. Furthermore, the transition process from pump mode to turbine mode is segmented into five stages based on the variations in the guide vanes (GV). The findings reveal that the rotation of GV triggers sharp fluctuations in static pressure, torque, and axial force. During stage four, the initiation of all three GV positions results in an increase in flow rate and torque, accompanied by a decrease in axial force. In stage two, the closure of GV leads to a decrease in pressure within the spiral casing (SC) and stay vanes (SV) domains, coupled with an increase in pressure in the bladeless zone, runner, and draft tube domains. Simultaneously, the pressure difference between both sides of the runner decreases significantly, directly causing a drop in torque and axial force. In stage three, GV closure interrupts the flow in the pump-turbine, resulting in significant backflow in the SC, SV, and runner domains, alongside high-speed circulation in the bladeless area. Moreover, the location of the high entropy production rate (EPR) value within the unit aligns with the reflux zone, indicating considerable energy loss attributable to reflux. The above research results will provide reference for the rapid switching of operating conditions of pump turbines in emergency situations.

Visual analytics (VA) technology has become a significant tool for business decision-makers to explore novel insights. One of its key features is analytical reasoning through interactive visualization that users have direct sensemaking in problem-solving processes. Few studies have examined how VA can be applied in business education for improving educational purpose. Social cognitive theory grounded in the current study as a framework to guide a qualitative exploration. The investigation was guided by two research questions: (1) What are the benefits and challenges of VA used in business education? (2) How do students interact with VA to improve knowledge construction in problem-solving? In-depth interviews and focus groups were conducted to derive data for thematic analysis from 25 informants. Three researchers conducted coding and data analysis through Nvivo 11.0. Five themes were identified in the corpus of data: (1) Perceived benefits to learning, (2) Prerequisite conditions, (3) Application context, (4) Motivational engagement, and (5) Knowledge construction. The study suggests that incorporating VA technology with problem-solving facilitates students' knowledge organisation and acquisition.

In the realm of marine science and engineering, hydrofoils play a pivotal role in the efficiency and performance of marine turbines and water-jet pumps. In this investigation, the boundary layer characteristics of an NACA0009 hydrofoil with a blunt trailing edge are focused on. The effectiveness of both the two-equation gamma theta (γ-Reθt) transition model and the one-equation intermittency (γ) transition model in forecasting boundary layer behavior is evaluated. When considering natural transition, these two models outperform the shear stress transport two-equation (SST k-ω) turbulence model, notably enhancing the accuracy of predicting boundary layer flow distribution for chord-length Reynolds numbers (ReL) below 1.6 × 106. However, as ReL increases, both transition models deviate from experimental values, particularly when ReL is greater than 2 × 106. The results indicate that the laminar separation bubble (LSB) is sensitive to changes in angles of attack (AOA) and ReL, with its formation observed at AOA greater than 2°. The dimensions of the LSB, including the initiation and reattachment points, are found to contract as ReL increases while maintaining a constant AOA. Conversely, an increase in AOA at similar ReL values leads to a reduced size of the LSB. The findings are essential for the design and performance optimization of water-jet pumps, particularly in predicting and flow separation and transition phenomena.

The digital transformation of metrology is one of the most active activities in the field of metrology at present, where the digital calibration certificate (DCC) being developed is the topic receiving the most concern in the current digital transformation. In practical industrial applications, the issue of storage carrier for the DCC plays a crucial role in its promotion and implementation. To address this issue, a DCC meta-model called DCC-Lite schema has been designed along with a corresponding processing method. This solution involves compressing and segmenting the DCC to make it suitable for storage using RFID tags. These RFID tags are affixed to the instruments and accompany them throughout their usage. Additionally, the DCC-RFID processing system has been developed to validate the effectiveness of the DCC meta-model and its corresponding processing method within a wireless temperature acquisition system. Experimental results demonstrate that the system successfully reads and writes the DCC stored within the RFID tag group. Furthermore, it enables automated parsing of the DCC calibration data by the machine and real-time compensation of measurement data to reduce measurement errors.

Background: The contextual and interactive learning research was motivated by the need to enhance the healthcare training effect of caregivers of patients with suspected COVID-19 infection during quarantine. However, there is a lack of effective approaches to integrating mobile contextual learning into interactive learning. Objectives: Therefore, this study developed a mobile augmented reality-integration contextual interactive healthcare training system, and then investigated the effects of the proposed system on anxiety, learning effects, perceived support and self-efficacies. Methods: To validate the effectiveness of the system, we conducted a quasi-experiment with a sample of 91 caregivers of patients with suspected COVID-19 infection. Results and conclusions: Results showed that the experimental group with the developed system was superior to the control group with e-pamphlet instruction in mobile devices, in terms of learning effect, perceived support, self-efficacies and reduction of anxiety during quarantine. Therefore, the mobile contextual interactive healthcare training system could be useful to improve caregivers' self-efficacies as well as their ability to care for patients in the context of COVID-19 infection prevention. Implications: This is one of the few studies of the effective approach for technology-enhanced healthcare education in the COVID-19 pandemic. Some corresponding suggestions are proposed: implementing mobile contextual interactive training activities to enhance caregivers' knowledge, skills and self-efficacies; involving social interactions to relieve caregivers' anxiety; providing professional communications and support while facing difficulties in taking care of patients with suspected COVID-19 infection.

Air-core vortices are a ubiquitous phenomenon in the intakes of hydropower stations. Due to the transient and instability of two-phase vorticial flow, the prediction of air-core vortex formation is challenging, and understanding of the instability mechanism remains elusive. In this study, the large eddy simulation (LES) method and a coupled level-set and volume-of-fluid (CLSVOF) method are performed to study air-core vortex formation in a benchmark reservoir with a horizontal intake pipe. The process of air-core vortex formation can be classified into an inception stage, an instability stage, and a stability stage. In the instability stage, the surface vortex repeatedly goes through the process of inception, enhancement, attenuation, and extinction. The movement of the counterrotating secondary vortices and water surface level fluctuation plays a negative role in air-core vortex formation. The additional motion generated by the counterrotating pair drives the pair to the back wall. The main vortex undergoes attenuation due to the stretching/tilting effects induced by the secondary vortex. Water level fluctuations briefly increase the submergence depth, which in turn reduces the vertical velocity gradient and vertical vorticity, destabilizing the vortex. The perturbation of the air-core vortex by water level fluctuations is present only at the beginning of the instability stage.

Traditional numerical simulation techniques, such as sliding mesh, dynamic mesh, and others, have many limitations in dealing with flow simulation with the large-scale movement of solid boundaries, which is the case for simulating the flow of complex-shaped hydraulic turbomachinery such as propellers, pumps, and turbines. The immersed boundary (IB) method provides a new approach to solve the above-mentioned limitations. Therefore, this study proposes a sharp-interface IB method based on the level-set function that is suitable for simulating the flow through turbomachinery with complex geometries. This method is applied to actual three-dimensional numerical simulations of high-Reynolds number propellers using an in-house computational fluid dynamics solver. The results show that the proposed method can provide comparatively accurate predictions of unsteady load coefficients within the propeller flow passage and capture the correct propeller wake characteristics as well as the interaction between the propeller wake and free surface. This study is aimed at providing a theoretical basis and engineering reference for the application of the IB method in engineering numerical simulations.

Research has shown that massively multiplayer online role-playing games (MMORPGs) have the potential to offer language learning opportunities. However, there is a dearth of research exploring student attitudes about the potential of these games for language learning. We used the language learning principles framework proposed by Brown and Lee (2015) to explore the attitudes of informal Iranian EFL gamers about the potential of the MMORPG environment for language learning. Using a mixed-methods approach, data collected by means of a questionnaire (N = 500) and semi-structured interviews (N = 20) showed that participant attitudes aligned with eight language learning principles (i.e. autonomy, transfer, reward, self-regulation, identity and investment, interaction, languaculture, and agency). The findings of the study highlight the potential of the MMORPG environment for language learning. Parents and EFL teachers should consider the potential affordances of the MMORPG environment as an alternative or complement to formal English language learning environments. [ABSTRACT FROM AUTHOR]

The digital twin, as the decision center of the automated drilling system, incorporates physical or data-driven models to predict the system response (rate of penetration, down-hole circulating pressure, drilling torques, etc.). Real-time drilling torque prediction aids in drilling parameter optimization, drill string stabilization, and comparing the discrepancy between observed signal and theoretical trend to detect down-hole anomalies. Due to their inability to handle huge amounts of time series data, current machine learning techniques are unsuitable for the online prediction of drilling torque. Therefore, a new way, the just-in-time learning (JITL) framework and local machine learning model, are proposed to solve the problem. The steps in this method are: (1) a specific metric is designed to measure the similarity between time series drilling data and scenarios to be predicted ahead of bit; (2) parts of drilling data are selected to train a local model for a specific prediction scenario separately; (3) the local machine learning model is used to predict drilling torque ahead of bit. Both the model data test results and the field data application results certify the advantages of the method over the traditional sliding window methods. Moreover, the proposed method has been proven to be effective in drilling parameter optimization and pipe sticking trend detection. Finally, we offer suggestions for the selection of local machine learning algorithms and real-time prediction with this approach based on the test results. [ABSTRACT FROM AUTHOR]

Visual analytics technology enjoys a growing trend in data analysis and visualisation science. The potential of visual analytics application in classroom learning remains opaque. We integrated visual analytics tool in learning to examine higher-order thinking in terms of technology's innovation attributes, learning satisfaction, and epistemological beliefs advancement. A cross-sectional survey of 247 undergraduate business students was conducted in a south China university. Result suggests that three features of visual analytics shared variance in satisfactory learning. This satisfactory VA-assisted learning predicts business students' higher-order thinking, while the change in epistemological beliefs only occurs with satisfactory evaluation. Implications for education practitioners to adopt technological transformation have been provided.

Tangible objects are devices that connect physical objects and digital worlds through tangible user interfaces. With the availability of tangible objects in the market, teacher education courses should be updated to provide opportunities for pre-service teachers to engage in digital environments; by these means, they can make more informed decisions about their teaching. This paper explores the views of pre-service teachers regarding the use of tangible objects to facilitate early childhood learning, from within the framework of the theory of planned behaviour. The participants were teacher candidates specialising in early childhood education in a teacher-education programme in Macau. Various tangible objects in the market were presented to them and they were invited to design a lesson with them. After their implementation in a real classroom, the candidates' views on the value of and problems attending the use of tangible objects; these data were collected through open-ended questions. Content analysis was conducted to elucidate their views. The teacher candidates seemed to appreciate this modality but, at the same time, expressed concern regarding the new challenges of using tangible objects in their classroom.

Coronavirus (CoV) is a kind of zoonosis virus widely existing in nature. Since the outbreak of severe acute respiratory syndrome (SARS), the incidence of human CoV infections has increased, so as the severity of the infections. In particular, coronavirus disease 2019, which is still pandemic, has become a major public health issue of global concern. This review summarizes the classification, host of CoV and human diseases caused by CoV.

Abstract Pemphigus is an autoimmune skin disease. Ectopic lymphoid-like structures (ELSs) were found to be commonly present in the pemphigus lesions, presumably supporting in situ desmoglein (Dsg)-specific antibody production. Yet functional phenotypes and the regulators of Lymphoid aggregates in pemphigus lesions remain largely unknown. Herein, we used microarray technology to profile the gene expression in skin lesion infiltrating mononuclear cells (SIMC) from pemphigus patients. On top of that, we compared SIMC dataset to peripheral blood mononuclear cells (PBMC) dataset to characterize the unique role of SIMC. Functional enrichment results showed that mononuclear cells in skin lesions and peripheral blood both had over-represented IL-17 signaling pathways while neither was characterized by an activation of type I Interferon signaling pathways. Cell-type identification with relative subsets of known RNA transcripts (CIBERSORT) results showed that naïve natural killer cells (NK cells) were significantly more abundant in pemphigus lesions, and their relative abundance positively correlated with B cells abundance. Meanwhile, plasma cells population highly correlated with type 1 macrophages (M1) abundance. In addition, we also identified a lncRNA LINC01588 which might epigenetically regulate T helper 17 cells (Th17)/regulatory T cells (Treg) balance via the peroxisome proliferator-activated receptor (PPAR) signaling pathway. Here, we provide the first transcriptomic characterization of lesion infiltrating immune cells which illustrates a distinct interplay network between adaptive and innate immune cells. It helps discover new regulators of local immune response, which potentially will provide a novel path forward to further uncover pemphigus pathological mechanisms and develop targeted therapy.

The N-doped carbon nanofiber coated graphene nanosheets (NFGNs) were designed and constructed using EGNs as the skeleton and PPy as the carbon source. The samples were characterized by SEM, XRD, Raman, FTIR, XPS and BET. The results show that the interconnected N-doped carbon nanofibers are uniformly coated on the surface of EGNs. The NFGNs-800 presents high-level nitrogen atom doping of 11.53% and large specific surface area of 477.65 m2·g-1. The capacitance performance test results show that the NFGNs-800 electrode material exhibits high specific capacitance of 323.3 F·g-1 (1.0 A·g-1) and good rate characteristic. NFGNs-800 supercapacitor shows high energy density of 87.1 Wh·kg-1 at power density of 10500 W·kg-1. The specific capacitance of the supercapacitor is 95.9% of the initial specific capacitance and the columbic efficiency still remains above 99% after 10000 constant current charge discharge cycles.

Abstract The ultra-low head pump stations often have bidirectional demand of water delivery, so there is a risk of runaway accident occurring in both conditions. To analyze the difference of the runaway process under forward runaway condition (FRC) and backward runaway condition (BRC), the whole flow system of a horizontal axial flow pump is considered. The Shear-Stress Transport (SST) k–ω model is adopted and the volume of fluid (VOF) model is applied to simulate the water surface in the reservoirs. Meanwhile, the torque balance equation is introduced to obtain the real time rotational speed, then the bidirectional runaway process of the pump with the same head is simulated. In addition, the vortex transport equation and swirl number are proposed to reveal the flow characteristics during the runaway process. The results show that the runaway process can be divided into five stages: the drop, braking, rising, convergence and runaway stages, according to the changing law of torque curve. In the rising stage, the pressure difference on the blade surface continues to increase, which contributes to the abnormal torque increase. In this stage, the flow hits the pressure surface (PS) at a faster speed enlarging the pressure on PS, and the flow separation takes place on the suction surface (SS) weakening the pressure on SS. During the convergence and runaway stage, the pulsation amplitude of torque and axial force under FRC is obviously larger than those under BRC. This is because the rotation frequency of the vortex rope is the same as main pressure fluctuation frequency in impeller under FRC, which enhances the pulsation amplitude. Whereas the vortices are broken due to the inhibitive effect from guide vanes under BRC.