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Rubrics can guide teachers to provide effective feedback and students' peer- and self-assessment. This paper examines the effect of rubric use in flipped learning activities on students' learning achievement, metacognitive awareness, and cognitive load through a quasi-experiment. A total of 83 university students were randomly assigned to an experimental group or a control group. The students in the experimental group were given rubrics in performing pre-class learning activities on the cloud platform, while those in the control group used rubrics in post-class assessment and modification of their finished works. The results show that rubric use can assist flipped learning by improving students' learning achievement and metacognitive awareness, while reducing their cognitive load. Using rubrics before in-class work can yield stronger benefits in raising metacognitive awareness and lessening cognitive load. Moreover, the study reveals that students tend to hold a generally favorable attitude toward rubric use. These findings imply that appropriate use of rubrics in flipped learning has the potential to create a more efficient and learner-friendly condition to enhance self-regulated learning.

The task of question matching/retrieval focuses on determining whether two questions are semantically equivalent. It has garnered significant attention in the field of natural language processing (NLP) due to its commercial value. While neural network models have made great strides and achieved human-level accuracy, they still face challenges when handling complex scenarios. In this paper, we delve into the utilization of different specializations encoded in different layers of large-scale pre-trained language models (PTMs). We propose a novel attention-based model called ERNIE-ATT that effectively integrates the diverse levels of semantics acquired by PTMs, thereby enhancing robustness. Experimental evaluations on two challenging datasets showcase the superior performance of our proposed model. It outperforms not only traditional models that do not use PTMs but also exhibits a significant improvement over strong PTM-based models. These findings demonstrate the effectiveness of our approach in enhancing the robustness of question matching/retrieval systems. [ABSTRACT FROM AUTHOR]

Current researches mainly focus on the participation of wind farms in primary frequency regulation, including overspeed load shedding control, propeller control and their coordinated control, etc. The frequency support is realized by reserving reserve capacity of wind turbines, but the influence of the dynamic characteristics of maximum power point tracking (MPPT) on the overall frequency regulation characteristics of wind turbines during frequency support is ignored. To this end, firstly, the frequency response model of the system is constructed, and the main factors that affect the frequency dynamic characteristics are revealed. Secondly, the principle of the grid-forming VSC with the function of self-inertial synchronization is introduced, the influence of the dynamic characteristics of MPPT on the frequency regulation characteristics of the wind turbine generator is clarified. Finally, based on the PSCAD/EMTDC electromagnetic transient simulation software platform, the influence of the dynamic characteristics of MPPT on the frequency regulation characteristics are verified by combining the inertia self-synchronous network control technology. The simulation results indicate that with the increase of setting of droop control, the decrease of output power of MPPT becomes large so as to weaken the frequency support capability. [ABSTRACT FROM AUTHOR]

Osteoporosis (OP) can result in slower bone regeneration than the normal condition due to abnormal oxidative stress and high levels of reactive oxygen species (ROS), a condition detrimental for bone formation, making the OP‐related bone healing a significant clinical challenge. As the osteogenic differentiation ability of bone marrow mesenchymal stem cells (BMSCs) is closely related to bone regeneration; currently, this study assessed the effects of Picein on BMSCs in vitro and bone regeneration in osteoporotic bone defect in vivo. Cell viability was determined by CCK‐8 assay. The production of (ROS), malonaldehyde, superoxide dismutase activities, and glutathione was evaluated by using commercially available kits, and a flow cytometry analysis was adopted to detect macrophage polarization. Osteogenic capacity of BMSCs was evaluated by alkaline phosphatase (ALP) activity, ALP staining, and Alizarin red S staining. The expression of osteogenic‐related proteins (OPN, Runx‐2, OCN) and osteogenic‐related genes (ALP, BMP‐4, COL‐1, and Osterix) were evaluated by Western blotting and real‐time PCR (RT‐PCR). In addition, proliferation, migration ability, and angiogenic capacity of human umbilical vein endothelial cells (HUVECs) were evaluated by EdU staining, scratch test, transwell assay, and tube formation assay, respectively. Angiogenic‐related genes (VEGF, vWF, CD31) were also evaluated by RT‐PCR. Results showed that Picein alleviated erastin‐induced oxidative stress, enhanced osteogenic differentiation capacity of BMSCs, angiogenesis of HUVECs, and protects cells against ferroptosis through Nrf2/HO‐1/GPX4 axis. Moreover, Picein regulate immune microenvironment by promoting the polarization of M2 macrophages in vitro. In addition, Picein also reduce the inflammation levels and promotes bone regeneration in osteoporotic bone defect in OP rat models in vivo. Altogether, these results suggested that Picein can promote bone regeneration and alleviate oxidative stress via Nrf2/HO‐1/GPX4 pathway, offering Picein as a novel antioxidant agent for treating osteoporotic bone defect. [ABSTRACT FROM AUTHOR]

While calcium phosphate cement (CPC) is recognized as one of the most likely substitutes for the conventional Polymethylmethacrylate (PMMA), there are very few studies about its intradiscal leakage consequences. Herein, the goal of our study was to examine the effect of CPC particles on the ERK (extracellular regulatory kinase) pathway in human nucleus pulposus cell (HNPC) degeneration. Different concentrations of CPC particles (0.00‰, 0.01‰, 0.05‰, 0.1‰ v/v) were added to human nucleus pulposus cell cultures. After 10 days of treatment, HNPC biological behaviors and degeneration degree were analyzed by CCK-8 assay, crystal violet staining, flow cytometer and western blot. The effect of CPC on the ERK pathway was also analyzed by western blot. After activating the ERK path by overexpressing Ras, HNPCs’ biological behaviors and degeneration degree were analyzed again. We found that CPC particles had a negative effect on human nucleus pulposus cells (HNPCs), which are mainly reflected in cell growth and the cell cycle. After activation of the ERK signaling pathway, the negative effects of CPC on cell growth and the cell cycle were significantly reduced and the degeneration degree of HNPCs was reversed. CPC particles can probably block the activation of the ERK pathway, thus causing the HNPCs’ degeneration.