In the wake of the restrictions imposed on social interactions due to the COVID-19 pandemic, traditional classroom education was replaced by distance education in many universities. Under the changed circumstances, students are required to learn more independently. The challenge for teachers has been to duly ascertain students’ learning efficiency and engagement during online lectures. This paper proposes an optimized lightweight convolutional neural network (CNN) model for engagement recognition within a distance-learning setup through facial expressions. The ShuffleNet v2 architecture was selected, as this model can easily adapt to mobile platforms and deliver outstanding performance compared to other lightweight models. The proposed model was trained, tested, evaluated and compared with other CNN models. The results of our experiment showed that an optimized model based on the ShuffleNet v2 architecture with a change of activation function and the introduction of an attention mechanism provides the best performance concerning engagement recognition. Further, our proposed model outperforms many existing works in engagement recognition on the same database. Finally, this model is suitable for student engagement recognition for distance learning on mobile platforms.

Objective: To synthesize evidence regarding the relationship between outdoor air pollution and risk of asthma exacerbations in single lag0 and lag1 exposure patterns. Methods: We performed a systematic literature search using PubMed, Embase, Cochrane Library, Web of Science, ClinicalTrials, China National Knowledge Internet, Chinese BioMedical, and Wanfang databases. Articles published until August 1, 2020 and the reference lists of the relevant articles were reviewed. Two authors independently evaluated the eligible articles and performed structured extraction of the relevant information. Pooled relative risks (RRs) and 95% confidence intervals (CIs) of lag0 and lag1 exposure patterns were estimated using random-effect models. Results: Eighty-four studies met the eligibility criteria and provided sufficient information for meta-analysis. Outdoor air pollutants were associated with increased risk of asthma exacerbations in both single lag0 and lag1 exposure patterns [lag0: RR (95% CI) (pollutants), 1.057(1.011, 1.103) (air quality index, AQI), 1.007 (1.005, 1.010) (particulate matter of diameter ≤ 2.5 μm, PM_2.5), 1.009 (1.005, 1.012) (particulate matter of diameter, PM₁₀), 1.010 (1.006, 1.014) (NO₂), 1.030 (1.011, 1.048) (CO), 1.005 (1.002, 1.009) (O₃); lag1:1.064(1.022, 1.106) (AQI), 1.005 (1.002, 1.008) (PM_2.5), 1.007 (1.004, 1.011) (PM₁₀), 1.008 (1.004, 1.012) (NO₂), 1.025 (1.007, 1.042) (CO), 1.010 (1.006, 1.013) (O₃)], except SO₂ [lag0: RR (95% CI), 1.004 (1.000, 1.007); lag1: RR (95% CI), 1.003 (0.999, 1.006)]. Subgroup analyses revealed stronger effects in children and asthma exacerbations associated with other events (including symptoms, lung function changes, and medication use). Conclusion: Outdoor air pollution increases the asthma exacerbation risk in single lag0 and lag1 exposure patterns. Trial registration: PROSPERO, CRD42020204097. https://www.crd.york.ac.uk/. Supplemental data for this article is available online at https://doi.org/10.1080/02770903.2021.2008429 .

Purpose: Choriocarcinoma is most commonly gestational (androgenetic or biparental) but can be of germ cell origin or can develop as a component of a somatic neoplasm (genetically related to the patient). The latter type are aggressive neoplasms for which the underlying genetic alterations are not well characterized. Experimental Design: To investigate the relationship between the different components of somatic neoplasms with choriocarcinomatous elements, the genetic differences between gestational and nongestational tumors, and identify potential targetable alterations, we analyzed 23 samples from 11 tumors, including five gynecologic-type somatic neoplasms with choriocarcinomatous differentiation (two to three different components each) and six pure choriocarcinomas, for somatic mutations, single-nucleotide polymorphisms, and PD-L1 expression. Results: In mixed tumors, gynecologic-type carcinoma components demonstrated lineage-characteristic and lineage-specific alterations, with choriocarcinomatous components sharing some of these as well as demonstrating novel alterations, supporting a clonal relationship with divergent differentiation of the choriocarcinoma from the somatic carcinoma. TP53 mutation only occurred in nongestational tumors. Diffuse PD-L1 expression was characteristic of choriocarcinoma in both pure and mixed tumors but not seen in the gynecologic-type carcinoma components. Conclusions: Given that the somatic carcinomatous and choriocarcinomatous components of mixed tumors have distinct genetic alterations and biomarker expression, separate analysis of these components is required to guide targeted therapy. High PD-L1 expression suggests a role for checkpoint inhibitor–based immunotherapy in tumors with a choriocarcinoma component. The underlying mechanisms by which cancer stem cells reprogram and initiate trophoblastic retrodifferentiation in some somatic tumors warrant further investigation.

In this paper, we investigate the current state and development of personalized smart immersive extended reality environments (PSI-XR). PSI-XR has gained increasing traction across various fields such as education, entertainment, and healthcare, offering customized immersive experiences that address users’ personalized needs. This study performs a systematic literature review by collecting and analyzing related journal and conference papers in the domain. Following a comprehensive search across three databases, which yielded 1276 papers, a refined selection of 94 publications was made to conduct an in-depth analysis of cutting-edge research in the field of PSI-XR. This review focused on examining application domains, relevant technologies, and smart techniques, including artificial intelligence, with particular emphasis on advancements in personalization. The study provides insights into prospective advancements while also identifying the opportunities and challenges in this evolving field. This review is beneficial for both researchers and developers interested in exploring the state-of-the-art personalized perspective in a smart immersive extended reality environment.

Facing the increasingly serious ageing problem, IT technology is being applied more and more to alleviate the increasing health demands of the elderly. Virtual reality (VR) games, in particular, have been shown to benefit the physical and mental health of the elderly. However, almost all consumer-level VR games address the general user, not considering the characteristics of the elderly, such as their particular needs regarding cognitive aspects and safety. In addition, the existing VR rowing games’ research typically focuses on athlete training or is based on a rowing machine. Extending on previous research, this paper proposes a conceptual design of a VR rowing game, VRrowing to provide a home exercise game for the elderly which benefits both physical and mental health. This research first analysed the relevant literature and existing VR exercise games for the elderly to find characteristics and their particular needs. Then, following design principles (in exercise games, human–computer interaction, and user interfaces (UIs)) for the elderly, this study proposed a conceptual design of VRrowing through the MDA framework (standing for mechanics, dynamics, and aesthetics). The results cover the system architecture, activities and tasks, patterns and roles, mechanics and structures, and UI examples. Based on comprehensive consideration of the results from relevant research and fostering strengths and circumventing weaknesses, VRrowing was designed as a sports game, aimed at the elderly according to their characteristics and needs, which fills the void of home VR rowing games for seniors’ exercise. This research has reference value for scientific research or development personnel in VR game applications and evaluations, especially for such games targeting the elderly.