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Solid‐state supercapacitors (SSCs) are emerging as one of the promising energy storage devices due to their high safety, superior power density, and excellent cycling life. However, performance degradation and safety issues under extreme conditions are the main challenges for the practical application. With the expansion of human activities, such as space missions, polar exploration, and so on, the investigation of SSC with wide temperature tolerance, high energy density, power density, and sustainability is highly desired. In this review, the effects of temperature on SSC are systematically illustrated and clarified, including the properties of the electrolyte, ion diffusion, and reaction dynamics of the supercapacitor. Subsequently, we summarize the recent advances in wide‐temperature‐range SSCs from the aspect of electrolyte modification, electrode design, and interface adjustment between electrode and electrolyte, especially with critical concerns on ionic conductivity and cycling stability. In the end, a perspective is presented, expecting to promote the practical application of the SSC in harsh conditions. [ABSTRACT FROM AUTHOR]

Federated learning (FL) is an attractive paradigm for privacy-aware distributed machine learning, which enables clients to collaboratively learn a global model without sharing clients' data. Recently, many strategies have been proposed to improve the generality of the global model and thus improve FL effect. However, existing strategies either ignore the fairness among clients or sacrifice performance for fairness. They cannot ensure that the gap among clients is as small as possible without sacrificing federated performance. To address this issue, we propose ParetoFed, a new local information aggregation method dedicated to obtaining better federated performance with smaller gap among clients. Specifically, we propose to use multi-objective hyperparameter optimization (HPO) algorithm to gain global models that are both fair and effective. Then, we send Pareto Optimal global models to each client, allowing them to choose the most suitable one as the base to optimize their local model. ParetoFed not only make the global models more fair but also make the selection of local models more personalized, which can further improve the federated performance. Extensive experiments show that ParetoFed outperforms existing FL methods in terms of fairness, and even achieves better federated performance, which demonstrates the significance of our method. [ABSTRACT FROM AUTHOR]

Abstract.Spearman’s footrule is a widely used tool to discover the relationship between two continuous random variables, mainly because of its robustness, natural interpretation, and simplicity of calculation. In this article, we propose a new test statistic based on the sum of squares of pairwise Spearman’s footrule, to test the mutual independence of a high dimensional random vector. The large sample properties of the proposed test method are established. Simulation results show that the new test has higher power than existing test methods under some circumstances. An example with real life data is discussed to illustrate the usefulness and effectiveness of the proposed test statistic. [ABSTRACT FROM AUTHOR]

AbstractThere are lots of methods for complete independence test for high-dimensional random vector. However, it is difficult for practitioners to choose a powerful test because the true alternative hypothesis is unknown. Combining the L2-type with the L∞-type test statistic, we propose a rank-based test method. From a technical point of view, the proposed test is distribution-free and consequently the corresponding critical values or p-values can be obtained by Monte Carlo methods. Compared with permutation or bootstrap test methods, the proposed test method saves calculation cost. Simulation results show that the resulting method has excellent performance with finite sample size. We also provide a real data application to demonstrate the practicality and effectiveness of the proposed test method. [ABSTRACT FROM AUTHOR]

Background Long-term care residents were among the most vulnerable during the COVID-19 pandemic. We estimated vaccine effectiveness of mRNA COVID-19 vaccines in Medicare nursing home residents aged ≥65 years during pre-Delta and high Delta periods. Methods We conducted a retrospective cohort study from 13 December 2020 to 20 November 2021 using Medicare claims data. Exposures included 2 and 3 doses of Pfizer-BioNTech and Moderna COVID-19 vaccines. We used inverse probability weighting and Cox proportional hazards models to estimate absolute and relative vaccine effectiveness. Results Two-dose vaccine effectiveness against COVID-19–related death was 69.8% (95% CI, 65.9%‒73.3%) during the pre-Delta period and 55.7% (49.5%‒61.1%) during the high Delta period, without adjusting for time since vaccination. We observed substantial waning of effectiveness from 65.1% (54.2%‒73.5%) within 6 months from second-dose vaccination to 45.2% (30.6%‒56.7%) ≥6 months after second-dose vaccination in the high Delta period. Three doses provided 88.7% (73.5%‒95.2%) vaccine effectiveness against death, and the incremental benefit of 3 vs 2 doses was 74.6% (40.4%‒89.2%) during high Delta. Among beneficiaries with a prior COVID-19 infection, 3-dose vaccine effectiveness for preventing death was 78.6% (50.0%‒90.8%), and the additional protection of 3 vs 2 doses was 70.0% (30.1%‒87.1%) during high Delta. Vaccine effectiveness estimates against less severe outcomes (eg, infection) were lower. Conclusions This nationwide real-world study demonstrated that mRNA COVID-19 vaccines provided substantial protection against COVID-19–related death. Two-dose protection waned after 6 months. Third doses during the high Delta period provided significant additional protection for individuals with or without a prior COVID-19 infection. [ABSTRACT FROM AUTHOR]

Highlights: Fe single-atom catalysts (h3-FNCs) with high loading, high catalytic activity and high stability were synthesized via a method capable of increasing both the metal loading and mass-specific activity by exchanging zinc with iron. The "density effect," derived from the sufficiently high density of active sites, has been discovered for the first time, leading to a significant alteration in the intrinsic activity of single-atom metal sites. The superior oxidase-like catalytic performance of h3-FNCs ensures highly effective bacterial eradication. The current single-atom catalysts (SACs) for medicine still suffer from the limited active site density. Here, we develop a synthetic method capable of increasing both the metal loading and mass-specific activity of SACs by exchanging zinc with iron. The constructed iron SACs (h3-FNC) with a high metal loading of 6.27 wt% and an optimized adjacent Fe distance of ~ 4 Å exhibit excellent oxidase-like catalytic performance without significant activity decay after being stored for six months and promising antibacterial effects. Attractively, a "density effect" has been found at a high-enough metal doping amount, at which individual active sites become close enough to interact with each other and alter the electronic structure, resulting in significantly boosted intrinsic activity of single-atomic iron sites in h3-FNCs by 2.3 times compared to low- and medium-loading SACs. Consequently, the overall catalytic activity of h3-FNC is highly improved, with mass activity and metal mass-specific activity that are, respectively, 66 and 315 times higher than those of commercial Pt/C. In addition, h3-FNCs demonstrate efficiently enhanced capability in catalyzing oxygen reduction into superoxide anion (O2·−) and glutathione (GSH) depletion. Both in vitro and in vivo assays demonstrate the superior antibacterial efficacy of h3-FNCs in promoting wound healing. This work presents an intriguing activity-enhancement effect in catalysts and exhibits impressive therapeutic efficacy in combating bacterial infections. [ABSTRACT FROM AUTHOR]

Trehalases (TREs), serving as crucial enzymes regulating trehalose and chitin metabolism in insects, represent prime targets for pest control strategies. We investigated the impact of three thioxothiazolidin compounds (1G, 2G, and 11G) on TRE activity and summarized their effects on the growth and development of Spodoptera frugiperda (Lepidoptera, Noctuidae). The experimental larvae of S. frugiperda were injected with the three thioxothiazolidin compounds (1G, 2G, and 11G), while the control group received an equivalent volume of 2% DMSO as a control. All three compounds had a strong effect on inhibiting TRE activity, significantly prolonging the pre-pupal development stage. However, compared with the 11G-treated group, the survival rate of larvae treated with 1G and 2G was significantly reduced by 31.11% and 27.78% respectively, while the occurrence of phenotypic abnormalities related to growth and development was higher. These results manifest that only the TRE inhibitors, 1G and 2G, modulate trehalose and chitin metabolism pathways of larvae, ultimately resulting in the failure molting and reduction of survival rates. Consequently, the thioxothiazolidin compounds, 1G and 2G, hold potential as environmentally friendly insecticides. [ABSTRACT FROM AUTHOR]

Conventional reinforced concrete shear walls are vulnerable to strong earthquakes with significant residual deformations, which substantially affect structural service and can even lead to structural collapse. Superelastic shape memory alloys (SMAs) are advanced materials that can realize strain recovery upon unloading. If SMAs can be used as reinforcing bars in structures, they can undergo large deformation without permanent deformation. This study presents a complementary and synergistic material system that integrates SMA with damage-tolerant engineered cementitious composites (ECCs) to minimize residual displacement and mitigate concrete damage. This study explored the seismic performance of shear walls using SMA and ECC in the plastic hinge region. Reverse cyclic loading tests were performed on four specimens to demonstrate the feasibility of this method. The specimens included a conventional steel-reinforced concrete shear wall (SW-R-C), steel-reinforced ECC shear wall (SW-R-ECC), SMA-reinforced concrete shear wall (SW-SMA-C), and SMA-reinforced ECC shear wall (SW-SMA-ECC). The results show that the SW-SMA-C specimen exhibited remarkable self-centering capability of more than 85% even after a large deformation, compared to SW-R-C. Furthermore, reduced damage and better ductility were observed in the SW-SMA-ECC specimen in addition to reduced residual displacement. The proposed approach indicated that SMA combined with ECC is more effective in mitigating plastic hinge damage and minimizing residual displacements, which could improve the seismic performance of shear walls. [ABSTRACT FROM AUTHOR]

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The direct detection of gravitational waves offers a powerful tool to explore the nature of gravity and the structure of space-time. This paper focuses on the capabilities of space-based gravitational wave detectors in testing space-time non-commutativity. Our findings indicate that TianQin has the potential to impose constraints on the non-commutative scale at a sub-Planckian level using massive black hole binaries. Additionally, we have developed a pipeline tailored to this specific topic. [ABSTRACT FROM AUTHOR]

In response to the increasing attention paid to environmental governance and leadership mobility, this study explores the interactions between leadership mobility and environmental governance performance. From the perspective of networks, this study aims to determine whether leadership mobility networks shape environmental governance outcomes. We argue that leadership transfer networks affect local water governance performance, which is particularly evident when leadership mobility occurs between cities with similar institutional environments. We collected managers' career data and water governance performance from forty-one cities located in the Pan-Yangtze River Delta region in China from 2011 to 2015. Methodologically, we employ spatial temporal autoregressive models to test the hypotheses and confirm the effects of the leadership transfer network on the homogeneity of water governance performance across the region. Theoretically, this study advances the institutional collective action framework in regional water governance by providing supplementary mechanisms from the perspective of agent network diffusion. [ABSTRACT FROM AUTHOR]

Quality of Service (QoS) routing protocol is a hot topic in the research field of wireless sensor networks (WSNs). However, the task of identifying an optimal path that simultaneously meets multiple QoS constraints is acknowledged as an NP-hard problem, with its complexity intensifying in proportion to the network's nodal count. Therefore, a novel heuristic multi-objective trust routing method, the Levy Chaos Adaptive Snake Optimization-based Multi-Trust Routing Method (LCASO-MTRM), is proposed, aiming to enhance link bandwidth while simultaneously reducing latency, packet loss, and energy consumption. The proposed method incorporates innovative chaos and adaptive operators within the LCASO framework. The chaos operator enhances population diversity, expands the solution space, and accelerates the search process. Meanwhile, the adaptive operator improves convergence, enhances robustness, and effectively prevents stagnation. Additionally, this paper introduces a novel multi-objective QoS routing model that integrates a link trust mechanism, allowing for a more accurate assessment of link trust levels and a precise reflection of the current link status. The effectiveness of LCASO-MTRM is demonstrated through simulation comparisons with the Improved Particle Swarm Optimization (IPSO), Improved Artificial Bee Colony Algorithm (IABC), and Cloned Whale Optimization Algorithm (CWOA). Simulation results demonstrate that LCASO-MTRM significantly reduces energy consumption by 49.53%, latency by 22.56%, and packet loss by 40.21%, while increasing bandwidth by 6.13%, outperforming the other algorithms., (© 2024. The Author(s).)