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Background: The impact of mobile technology usage on student learning in various educational stages has been the subject of ongoing empirical and review research. The most recent meta-analyses on various types of mobile technology use for potential benefits of learning covered the empirical studies up to about nine years ago. Since then, the use of mobile technology in primary and secondary education has increased tremendously, and numerous empirical studies have been conducted on this topic, but their conclusions were inconsistent. Objectives: The purpose of this systematic review is to re-examine this issue by meta-analyzing the empirical research studies from the last nine years, with a focus on cognitive, affective, and behavioral learning outcomes in primary and secondary education, and to examine the potential moderators that may have contributed to the heterogeneity across findings. Methods: Based on our inclusion and exclusion criteria, we found 85 studies of 78 peer-reviewed papers (N = 9157) from electronic databases and major journals in educational technology and mobile learning between 2014 and 2022. We then examined 15 moderators that were expected to affect student learning outcomes. Results and Conclusions: Compared with traditional technology and non-technology groups, using mobile technology produced medium positive and statistically significant effects on primary and secondary students' learning, in terms of cognitive (g = 0.498, 95% CI [0.382, 0.614]), affective (g = 0.449, 95% CI [0.301, 0.598]) and behavioural (g = 0.339, 95% CI [0.051, 0.627]) learning outcomes. Further moderator analyses revealed that student factors (i.e., community type, students' socioeconomic status), learning process (i.e., hardware used, student-to-hardware ratio, teaching method) and study quality (i.e., learning topic/content equivalence, degree of technology use in the control group) were among the variables that moderated the summary effect sizes for at least one learning outcome dimension significantly. The findings and their implications for researchers, policymakers and practitioners are discussed.

Developing efficient catalysts is of paramount importance to oxygen evolution, a sluggish anodic reaction that provides essential electrons and protons for various electrochemical processes, such as hydrogen generation. Here, we report that the oxygen evolution reaction (OER) can be efficiently catalyzed by cobalt tetrahedra, which are stabilized over the surface of a Swedenborgite-type YBCo4O7 material. We reveal that the surface of YBaCo4O7 possesses strong resilience towards structural amorphization during OER, which originates from its distinctive structural evolution toward electrochemical oxidation. The bulk of YBaCo4O7 composes of corner-sharing only CoO4 tetrahedra, which can flexibly alter their positions to accommodate the insertion of interstitial oxygen ions and mediate the stress during the electrochemical oxidation. The density functional theory calculations demonstrate that the OER is efficiently catalyzed by a binuclear active site of dual corner-shared cobalt tetrahedra, which have a coordination number switching between 3 and 4 during the reaction. We expect that the reported active structural motif of dual corner-shared cobalt tetrahedra in this study could enable further development of compounds for catalyzing the OER.

Metal leaching during water oxidation has been typically observed in conjunction with surface reconstruction on perovskite oxide catalysts, but the role of metal leaching at each geometric site has not been distinguished. Here, we manipulate the occurrence and process of surface reconstruction in two model ABO3 perovskites, i.e., SrSc0.5Ir0.5O3 and SrCo0.5Ir0.5O3, which allow us to evaluate the structure and activity evolution step by step. The occurrence and order of leaching of Sr (A-site) and Sc/Co (B-site) were controlled by tailoring the thermodynamic stability of B-site. Sr leaching from A-site mainly generates more electrochemical surface area for the reaction, and additional leaching of Sc/Co from B-site triggers the formation of a honeycomb-like IrOxHy phase with a notable increase in intrinsic activity. A thorough surface reconstruction with dual-site metal leaching induces an activity improvement by approximately two orders of magnitude, which makes the reconstructed SrCo0.5Ir0.5O3 among the best for water oxidation in acid.

Exploring robust catalysts for water oxidation in acidic electrolyte is challenging due to the limited material choice. Iridium (Ir) is the only active element with a high resistance to the acid corrosion during water electrolysis. However, Ir is rare, and its large-scale application could only be possible if the intrinsic activity of Ir could be greatly enhanced. Here, a pseudo-cubic SrCo0.9Ir0.1O3-δ perovskite, containing corner-shared IrO6 octahedrons, is designed. The Ir in the SrCo0.9Ir0.1O3-δ catalyst shows an extremely high intrinsic activity as reflected from its high turnover frequency, which is more than two orders of magnitude higher than that of IrO2. During the electrochemical cycling, a surface reconstruction, with Sr and Co leaching, over SrCo0.9Ir0.1O3-δ occurs. Such reconstructed surface region, likely contains a high amount of structural domains with corner-shared and under-coordinated IrOx octahedrons, is responsible for the observed high activity.

Background: Cardiometabolic multimorbidity (CM) is emerging as a global health challenge. This study investigated the potential impact of muscle strength on the risk of CM in middle-aged and older Chinese adults. Methods: In total, 7610 participants were identified from the China Health and Retirement Longitudinal Study (CHARLS). Muscle strength was measured by absolute, relative grip strength (normalized for body mass index) and chair-rising time which were classified into three categories according to tertiles stratified by gender. Cox proportional hazards models were adopted to evaluate the effect of muscle strength on CM. Results: During follow-up, 235(3.76%) participants from none cardiometabolic diseases (CMD), 140 (19.23%) from diabetes, 119 (21.17%) from heart disease, and 22 (30.56%) from stroke progressed to CM. In participants who had low relative grip strength, CM was more likely to occur in individuals with heart disease at baseline (HR: 1.89, 95%CIs: 1.10 to 3.23). Those with high chair-rising time had a higher risk of CM than those with low chair-rising time in the individuals with diabetes (HR: 1.85, 95%CIs:1.20 to 2.86) and with heart disease (HR: 1.67, 95%CIs:1.04 to 2.70). However, we did not observe an association between muscle strength and CM in participants without CMD or with stroke at baseline. Conclusions: In Chinese middle-aged and older adults, low relative grip strength was associated with a higher risk of CM in individuals with heart disease, while high chair-rising time was associated with a higher risk of CM in individuals with diabetes or heart disease. [ABSTRACT FROM AUTHOR]

As China transitions into a deeply aging society, the elderly population's growth has driven a rapid increase in elderly care institutions and facilities during the "13th Five-Year Plan" period, rising by over 235% compared to the "12th Five-Year Plan". The ongoing normalization of COVID-19 prevention measures has underscored the urgent need to improve natural ventilation in elderly care residential facilities. This study conducted empirical surveys to assess the current state of natural ventilation in typical elderly care facilities and analyzed the architectural elements influencing it. By examining the needs and preferences of the elderly for natural ventilation, two basic living space layout types were identified through typological analysis. Suitable CFD simulation software was then employed to model key elements, and effective methods to enhance ventilation were summarized. This study found that modifying the floor plan to reduce the depth of south-facing rooms to 8.4 m, relocating external openings to the center of the rooms, adjusting the ratio of ventilation openings to room area to greater than 1/12, and adding 0.5 m high windows facing internal traffic roads can significantly improve indoor ventilation while maintaining privacy. Furthermore, placing the main activity and resting areas of the elderly in well-ventilated zones with minimal drafts can enhance both comfort and ventilation effectiveness. The research provides a scientific basis and methodological guidance for the construction and renovation of elderly care residential facilities. [ABSTRACT FROM AUTHOR]

Dendrites and side reactions of Zn anodes severely restrict the application of aqueous Zn‐based batteries for grid‐scale energy storage. While surface/interface modification strategies have shown some progress in improving Zn anode reversibility, they still fall short in addressing the overall regulation and intrinsic mechanisms from the bulk‐phase perspective. Herein, a bulk‐phase composite Zn/CNTs anodes fabricated by a powder‐metallurgy‐based strategy is introduced. Benefiting from the regulation of grain boundary engineering on local electric conductivity, electric field distributions, and Zn atom absorption energy, the Zn/CNTs anodes effectively suppress dendrite growth and enhance corrosion resistance during Zn stripping/plating cycles. Symmetrical cells equipped with Zn/CNT4 anodes exhibit extended cycling stability with minimal voltage hysteresis (only 22 mV). Furthermore, the full cells incorporating Zn/CNT4 with commercial MnO2 demonstrate superior rate performance and specific capacitance retention after 500 h cycling. This breakthrough opens up new avenues for optimizing metallic anodes at the bulk phase level using powder metallurgy, enabling scalable manufacturing processes, and providing valuable insights for various metal anode systems. [ABSTRACT FROM AUTHOR]