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The role of teachers is an important element of online project-based learning courses. Based on the Community of Inquiry framework, this study examined how students' perceptions of teaching presence, through social presence and cognitive presence, were related to their evaluations of online project-based learning. A 16-week online project-based legal education course was implemented. During the course, students engaged in two small group activities and created two final products. Survey data were collected twice from 38 and 41 students in two course phases. Results from partial least squares analyses revealed that teaching presence was directly related to students' evaluations in the early stage of the course and indirectly related to students' evaluations, through the effects of social presence, in the entire course. Practical implications for teachers and suggestions for further studies are provided.

One promising way to cope with changing requirements from the labor market in the domain of Science, Technology, Engineering and Mathematics (STEM), but also to keep the field up to date, to start innovations and to advance the STEM domain as such is the use of student labs. In these labs, students work together in small groups imitating professional practice of design and technology workers. More insights are needed in what competences student labs in the STEM domain address and what the implications would be for the design of student labs. A review of empirical studies on student labs and additional literature indicate that five generic competences are addressed in most student labs: Collaboration, communication, problem solving, critical thinking, and creativity. In order to effectively enhanced these competences, student labs should be designed as authentic productive learning environments based on three design principles: (1) Realistic, complex task situations, (2) Multidisciplinarity, and (3) Social interaction. IoT Rapid Proto Labs are examples of such a student labs, in which cross-border multidisciplinary teams of students, teachers (coaches), and practitioners jointly develop solutions to challenging IoT applications (Internet-connected objects), add value for enterprises, and strengthen the employability, creativity and career prospects of students.

Project-based learning (PjBL) engages students in knowledge acquisition, application, and construction through artefact development. Based on the Community of Inquiry framework, this study characterized college students' social and cognitive presences in online PjBL and examined how presence was related to their academic performance. Twenty-four groups of students participated in a 3-week project via WeChat discussion groups and created a final product. Transcripts of students' online discourse were collected and analysed by a coding scheme. The quality of students' artefacts was evaluated by a grading rubric. Descriptive results showed that the component of affectiveness and the level of exploration accounted for the majority of students' social and cognitive presences, respectively. Stepwise regression analyses revealed that certain components and sub-components of students' social presence, and levels and sub-levels of their cognitive presence were positively associated with their academic performance. Practical implications for teachers and suggestions for further research are provided.

Due to the presence of internal defects such as voids in the composites manufactured by material extrusion additive manufacturing (MEX AM), the mechanical properties of the composites are significantly below the theoretical optimum. Under this circumstance, this paper is intended to investigate the effects of nozzle feeding angles and to analyze the void formation and evolution of multiphase flow, in which systematic computational fluid dynamics numerical simulations are conducted. The volume of fluid model and overset grid method are used to simulate the extrusion deposition process of carbon fiber-reinforced polymer composites, and the Carreau model is used to represent the shear-thinning behavior of molten polymer. The numerical method is validated against previously experimental and numerical simulation data. The numerical results show that the key factor leading to void formation is the vortices caused by fiber oscillation. The intense vortex at the front end of the fibers disrupts the interface between molten polymer and air, creating a beneficial condition for air to enter. Nozzle tilting can effectively reduce the probability of void formation by decreasing the fiber oscillation velocity. The results of the present study provide insights into the development and optimization of printer nozzles to enable the printing of longer fibers with less probability of potential void formation. [ABSTRACT FROM AUTHOR]

In recent years, the safety issues of high-speed railways have remained severe. The intrusion of personnel or obstacles into the perimeter has often occurred in the past, causing derailment or parking, especially in the case of bad weather such as fog, haze, rain, etc. According to previous research, it is difficult for a single sensor to meet the application needs of all scenario, all weather, and all time domains. Due to the complementary advantages of multi-sensor data such as images and point clouds, multi-sensor fusion detection technology for high-speed railway perimeter intrusion is becoming a research hotspot. To the best of our knowledge, there has been no review of research on multi-sensor fusion detection technology for high-speed railway perimeter intrusion. To make up for this deficiency and stimulate future research, this article first analyzes the situation of high-speed railway technical defense measures and summarizes the research status of single sensor detection. Secondly, based on the analysis of typical intrusion scenarios in high-speed railways, we introduce the research status of multi-sensor data fusion detection algorithms and data. Then, we discuss risk assessment of railway safety. Finally, the trends and challenges of multi-sensor fusion detection algorithms in the railway field are discussed. This provides effective theoretical support and technical guidance for high-speed rail perimeter intrusion monitoring. [ABSTRACT FROM AUTHOR]

At present, there are no official approved drugs for improving muscle endurance. Our previous research found acute phase protein orosomucoid (ORM) is an endogenous anti‐fatigue protein, and macrolides antibiotics erythromycin can elevate ORM level to increase muscle bioenergetics and endurance parameters. Here, we further designed, synthesized and screened a new erythromycin derivative named HMS‐01, which lost its antibacterial activity in vitro and in vivo. Data showed that HMS‐01 could time‐ and dose‐dependently prolong mice forced‐swimming time and running time, and improve fatigue index in isolated soleus muscle. Moreover, HMS‐01 treatment could increase the glycogen content, mitochondria number and function in liver and skeletal muscle, as well as ORM level in these tissues and sera. In Orm‐deficient mice, the anti‐fatigue and glycogen‐elevation activity of HMS‐01 disappeared. Therefore, HMS‐01 might act as a promising small molecule drug targeting ORM to enhance muscle endurance. [ABSTRACT FROM AUTHOR]

In this paper, the drag coefficient (Cd), lift coefficient (Cl), and torque coefficient (Ct) of rotating non-spherical particles in shear-thinning non-Newtonian fluids are investigated based on particle-resolved direct numerical simulation. The Carreau model is used to describe the rheological behavior of non-Newtonian fluids, and the numerical model is validated against previously published data. Then, the effects of aspect ratio (Ar), spin number (Spa), flow index (n), and Carreau number (Cu) on Cd, Cl, and Ct of rotating non-spherical particles are investigated at different Reynolds numbers (Re). The numerical results show that the closer the particles are to the spherical shape, the smaller the fluctuations of Cd, Cl, and Ct curves. The peaks and valleys of Cd, Cl, and Ct of oblate and prolate ellipsoidal particles are reversely distributed. The fluctuations of Cd and Cl curves increase with increasing Spa. Cd decreases with increasing Spa at low Re, contrary to Newtonian fluids' results. Cd and Ct decrease with increasing shear-thinning properties, Cl increases with increasing shear-thinning properties, and the effect of shear-thinning properties decreases with increasing Re. The variation of viscosity and pressure is the main reason for the variation of Cd, Cl, and Ct under different variables. Predictive correlations of Cd and Ct are established based on Re, Spa, n, Cu, and α. The findings indicate that particle rotation and shear-thinning properties must be considered when evaluating particle-fluid interactions, which provide important guidance for predicting and controlling the orientation and distribution of non-spherical particles in non-Newtonian fluids. [ABSTRACT FROM AUTHOR]

A discrete element method (DEM) model for deformable particles is established and adopted to investigate the Jenike shear process of flexible cylindrical particles with different aspect ratios (4 < Ar < 6). The DEM model is firstly validated against both experimental data and analytic solutions. Then, numerical simulations are carried out and the effects of particles shape and deformation on their friction behavior are investigated through a particle‐scale analysis on particle deformation, coordinate number, contact forces, orientation and internal friction angle. Comparative results between flexible and rigid particles under the same conditions show that the shear stress increases almost linearly with the normal load regardless of particle stiffness or shape. For both rigid and flexible particles, the shear stress and internal friction angle increase with Ar. The shear stress and internal friction angle of the flexible particles are higher than those of the rigid ones especially when Ar = 6. The latter has more inter‐particle contacts but the former has stronger contact forces. When Ar = 4 and 5, the flexible particles without many initial deformations will deform significantly during the shear process with a complex reconfiguration taking place. However, when Ar = 6, the initial deformation and internal forces of the flexible particles only change slightly during the shear process. It is thus believed that the high shear stress and internal friction angle of the flexible particles with Ar = 6 are caused by their solid packing structure which strongly enhances the capability of the particle flow to resist shear. The current knowledge will be helpful for improving the kinetic theories for granular flow for complex irregular particle flows. [ABSTRACT FROM AUTHOR]

Intimate partner violence (IPV) is common in men who have sex with men (MSM). MSM also face increased risk of human immunodeficiency virus infection. However, it is not known whether IPV experience of MSM in China would affect their attitudes toward pre-exposure prophylaxis (PrEP) use. A cross-sectional study was conducted to explore the associations between different types of IPV and willingness to use PrEP in a sample of 608 MSM from November 2018 to May 2019 in Chengdu, China. Univariate and multivariate logistic regression analyses were used to explore the associations between different types of IPV and willingness to use PrEP. The average age of the participants was 31.8 ± 12.3 years, 48.9% of them were aware of PrEP before this study, and only 7.2% were aware of long-acting injectable PrEP (LAI-PrEP). The overall willingness to use any type of PrEP in the next 6 months was 82.2%. Approximately one third of the participants (n = 198) had experienced at least one type of IPV. We found that experience of sexual perpetration was negatively associated with the willingness to use on-demand PrEP (adjusted odds ratio [ORa] = 0.33, 95% CI = 0.16–0.67) and the overall willingness to use any type of PrEP (ORa = 0.31, 95% CI = 0.15–0.64). The willingness to use LAI-PrEP also had negative associations with any type of monitoring IPV (ORa = 0.58, 95% CI = 0.38–0.91), controlling victimization (ORa = 0.41, 95% CI = 0.21–0.82), and emotional victimization (ORa = 0.58, 95% CI = 0.35–0.97). The findings of this study demonstrate that IPV experiences are negatively associated with willingness to use PrEP among MSM, suggesting that PrEP promotion programs should consider IPV screening and develop explicit intervention strategies for both perpetrators and victims. [ABSTRACT FROM AUTHOR]

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Aims: To examine the effectiveness of Self-Help Plus (SH+) as an intervention for alleviating stress levels and mental health problems among healthcare workers., Methods: This was a prospective, two-arm, unblinded, parallel-designed randomised controlled trial. Participants were recruited at all levels of medical facilities within all municipal districts of Guangzhou. Eligible participants were adult healthcare workers experiencing psychological stress (10-item Perceived Stress Scale scores of ≥15) but without serious mental health problems or active suicidal ideation. A self-help psychological intervention developed by the World Health Organization in alleviating psychological stress and preventing the development of mental health problems. The primary outcome was psychological stress, assessed at the 3-month follow-up. Secondary outcomes were depression symptoms, anxiety symptoms, insomnia, positive affect (PA) and self-kindness assessed at the 3-month follow-up., Results: Between November 2021 and April 2022, 270 participants were enrolled and randomly assigned to either SH+ ( n = 135) or the control group ( n = 135). The SH+ group had significantly lower stress at the 3-month follow-up ( b = -1.23, 95% CI = -2.36, -0.10, p = 0.033) compared to the control group. The interaction effect indicated that the intervention effect in reducing stress differed over time ( b = -0.89, 95% CI = -1.50, -0.27, p = 0.005). Analysis of the secondary outcomes suggested that SH+ led to statistically significant improvements in most of the secondary outcomes, including depression, insomnia, PA and self-kindness., Conclusions: This is the first known randomised controlled trial ever conducted to improve stress and mental health problems among healthcare workers experiencing psychological stress in a low-resource setting. SH+ was found to be an effective strategy for alleviating psychological stress and reducing symptoms of common mental problems. SH+ has the potential to be scaled-up as a public health strategy to reduce the burden of mental health problems in healthcare workers exposed to high levels of stress.