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Mechanical assembly courses are widely set up for mechanical and vehicle engineering majors. Teaching in these classes is traditionally presented in the form of 2-D lectures, which are ineffective for students to understand complex 3-D information. The study presented in this article aimed to investigate whether augmented reality (AR) could improve students' learning efficacy in a mechanical assembly course. An AR-based assembly instruction app on mobile devices was developed, and a comparative research approach was adopted. A total of 104 junior students from four classes on automotive engineering at Nanjing Forestry University participated in the experiment during their professional skill training course. The control group was provided with handouts as usual, and the experimental group was required to use AR instructions during the assembly processes. Several evaluation indicators, such as assembly quality and speed, were recorded and analyzed at the same time. The results showed that such indicators were significantly improved with the utilization of AR. In addition, a questionnaire was specifically designed and distributed to all the students at the end of the course. It was found that several learning factors, such as learning interest and academic achievements in the experimental group, showed a positive correlation.

A surface water body fed by groundwater is normally known as a terminal place of groundwater flow systems originating from precipitation recharge on highlands. The theory of Tóth predicted that these flow systems form a hierarchically nested structure of groundwater circulation in a composite basin. In this study, we will report new flow paths among groundwater flow systems that were unknown in Tóth's theory, identified as special seepage paths linking different surface water bodies. These seepage paths do not start from the groundwater table but can transmit water between lakes or streams that already serve as discharge zones of traditional local flow systems. As indicated in theoretical models and two real‐world cases, special seepage paths are developed if some parametric conditions are satisfied, especially when surface water bodies cut deeply below the water table or are large enough. Different surface water bodies or different river reaches can directly exchange water, chemicals and heat through deep seepage paths even when both surface and subsurface water divides exist between them. Special seepage paths may play a role in the regional scale hyporheic flow or contribute to inter‐basin groundwater flow. The knowledge of special seepage paths could greatly improve our conventional perception of surface water‐groundwater interaction, groundwater age and geochemical and heat transport at the river basin scale. [ABSTRACT FROM AUTHOR]

As smart materials, electrorheological elastomers (EREs) formed by pre-treating active electrorheological particles are attracting more and more attention. In this work, four Mg-doped strontium titanate (Mg-STO) particles with spherical, dendritic, flake-like, and pinecone-like morphologies were obtained via hydrothermal and low-temperature co-precipitation. XRD, SEM, Raman, and FT-IR were used to characterize these products. The results showed that Mg-STOs are about 1.5–2.0 μm in size, and their phase structures are dominated by cubic crystals. These Mg-STOs were dispersed in a hydrogel composite elastic medium. Then, Mg-STO/glycerol/gelatin electrorheological composite hydrophilic elastomers were obtained with or without an electric field. The electric field response properties of Mg-doped strontium titanate composite elastomers were investigated. We concluded that dendritic Mg-STO composite elastomers are high-performance EREs, and the maximum value of their energy storage was 8.70 MPa. The significant electrorheological performance of these products is helpful for their applications in vibration control, force transducers, smart structures, dampers, and other fields. [ABSTRACT FROM AUTHOR]

Purpose: This meta-analysis compared the efficacy and safety of Proximal Femoral Nail Antirotation (PFNA) and InterTan Nail in the treatment of intertrochanteric fractures. Given the high incidence of femoral intertrochanteric fractures in the elderly population and its impact on quality of life, choosing the most effective and safest surgical option is crucial. PFNA and InterTan are currently two commonly used techniques, but there is a lack of systematic evaluation comparing their safety and effectiveness. This study aims to fill this knowledge gap through Meta-analysis, providing clinicians with evidence-based treatment recommendations. Materials and methods: A computer search was used to search for published literature on PFNA and InterTan in the treatment of intertrochanteric fractures in PubMed (Medline), Web of Science, Embase, Cochrane Library (CENTRAL), Cinahl, CBM, and CNKI.A total of 853 related literatures were retrieved, and 15 literatures were finally included. Newcastle-Ottawa-Scale and Cochrane systematic review methodologies were used to assess the quality of the literature. Meta-analysis was performed using Review Manager 5.4 software, following data extraction. Results: The comparison found that during the surgical treatment of intertrochanteric fractures, the operation time, fluoroscopy time, and blood loss in the PFNA group were significantly shorter than those in the InterTan group, and the difference was statistically significant. In terms of postoperative complication rates, the InterTan group had a significant advantage over the PFNA group. Shaft fracture, varus collapse, cut out, screw migration, and pain of hip and thigh were the most likely to occur in the PFNA group, and the differences were all statistically significant. In terms of postoperative efficacy, the results of the PFNA group and the InterTan group were comparable, and there was no significant differences. Conclusions: When selecting surgical techniques for the treatment of femoral intertrochanteric fractures, it is necessary to conduct individualized assessments based on the patient's overall health status, surgical tolerance, and post-operative recovery needs. For patients who cannot tolerate long-term surgery or are in poor physical condition, PFNA may be more appropriate. While for patients who can tolerate long-term surgery or have more complex conditions, InterTan may be more suitable. [ABSTRACT FROM AUTHOR]