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In this study, VO2 nanoparticles were synthesized in a single step using a simple and rapid low-temperature combustion synthesis method. When used as the cathode electrode material for aqueous zinc-ion batteries. It exhibited excellent rate performance, with maximum capacities of 415 mAh g−1, 375 mAh g−1, and 350 mAh g−1 at current densities of 0.5 A g−1, 1 A g−1, and 2 A g−1, respectively. However, the cyclic performance was subpar. This study was conducted to investigate the capacity degradation, revealing the formation of plate-like Zn3V2O7(OH)2·2H2O (BZS) precipitates on the electrode surface during the cycling process. The H+ ions generated from the BZS precipitation co-intercalated with Zn2+ ions into the VO2 structure, thereby enhancing the battery specific capacity. Nevertheless, excessive H+ ions altered the electrolyte pH, resulting in vanadium dissolution and capacity degradation. Furthermore, the excessive buildup of BZS during the cycling process severely impacted ion transport, leading to capacity loss. [ABSTRACT FROM AUTHOR]

The catalytic access of silicon‐stereogenic organosilanes remains a big challenge, and largely depends on the desymmetrization of the symmetric precursors with two identical substitutes attached to silicon atom. Here we report the construction of silicon‐stereogenic organosilanes via catalytic kinetic resolution of racemic monohydrosilanes with good to excellent selectivity factors. Both Si‐stereogenic dihydrobenzosiloles and Si‐stereogenic monohydrosilanes could be efficiently accessed in one single operation via Rh‐catalyzed enantioselective intramolecular hydrosilylation, employing (R,R)‐Et‐DuPhos as the optimal ligand. This catalytic protocol features mild conditions, a low catalyst loading (0.1 mol % [Rh(cod)Cl]2), high stereoinduction (S factor up to 152), and excellent scalability. Moreover, further derivatizations led to the efficient synthesis of uncommon middle‐size (7‐ and 8‐membered) Si‐stereogenic silacycles. Preliminary mechanistic study indicates this reaction might undergo a modified Chalk–Harrod mechanism. [ABSTRACT FROM AUTHOR]

The construction of silicon‐stereogenic silanols via Pd‐catalyzed intermolecular C−H alkenylation with the assistance of a commercially available L‐pyroglutamic acid has been realized for the first time. Employing oxime ether as the directing group, silicon‐stereogenic silanol derivatives could be readily prepared with excellent enantioselectivities, featuring a broad substrate scope and good functional group tolerance. Moreover, parallel kinetic resolution with unsymmetric substrates further highlighted the generality of this protocol. Mechanistic studies indicate that L‐pyroglutamic acid could stabilize the Pd catalyst and provide excellent chiral induction. Preliminary computational studies unveil the origin of the enantioselectivity in the C−H bond activation step. [ABSTRACT FROM AUTHOR]

In mixed-field source localization, the physical properties of a sensor array, such as the degrees of freedom (DOFs), aperture, and coupling leakage, directly affect the accuracy of estimating the direction of arrival (DOA). Compared to conventional symmetric uniform linear arrays, symmetric non-uniform linear arrays (SNLAs) have a greater advantage in mixed-field source localization due to their larger aperture and higher DOF. However, current SNLAs require improvements in their physical properties through modifications to the array structure in order to achieve more accurate source localization estimates. Therefore, this study proposes a symmetric double-supplemented nested array (SDSNA), which translates nested subarrays based on symmetric nested arrays to increase the aperture and inserts two symmetric supplemented subarrays to fill the holes created by the translation. This method results in longer consecutive difference coarray lags and larger apertures. The SDSNA is compared to existing advanced SNLAs in terms of their physical properties and DOA estimation. The results show that, with the same number of sensors, the SDSNA has a higher DOF, a larger aperture, and smaller coupling, indicating the advantages of the SDSNA in terms of its physical properties. Under the same experimental conditions, the SDSNA has a lower root-mean-square error of source location, thus indicating better performance in terms of both DOA and distance estimation. [ABSTRACT FROM AUTHOR]

As a developing country with an agricultural economy as a pillar, Bangladesh is highly vulnerable to adverse effects of climate change, so the generation of high-resolution temperature maps is of great value for Bangladesh to achieve agricultural sustainable development. However, Bangladesh's weak economy and sparse meteorological stations make it difficult to obtain such maps. In this study, by mining internal features and links inside observed data, we developed an efficient data-driven downscaling technique to generate high spatial-resolution temperature distribution maps of Bangladesh directly from observed temperature data at 34 meteorological stations with irregular distribution. Based on these high-resolution historical temperature maps, we further explored a data-driven forecast technique to generate high-resolution temperature maps of Bangladesh for the period 2025–2035. Since the proposed techniques are very low-cost and fully mine internal links inside irregular-distributed observations, they can support relevant departments of Bangladesh to formulate policies to mitigate and adapt to climate change in a timely manner. [ABSTRACT FROM AUTHOR]

Electrochemical membranes (ECMs) and porous electrodes have gained much attention in a broad range of applications including water and wastewater treatment, energy production and storage, and carbon dioxide capture. Lab scale batch experiments (electrochemical stirred cells) are the baseline for developing ECMs and porous electrodes. We observed electrochemical dissolution of metal fasteners (alligator clips), used to hold porous conductive and non‐conductive membranes in batch electrochemical cells, despite being kept outside the electrolyte. The electrolyte migrated through the porous membranes by the action of capillary forces, forming a closed electrochemical circuit with the metal fasteners. This unexpected leaching can lead to misleading results for electrochemical experiments on porous electrodes and ECMs. In this study, we compared (1) porous membranes versus non‐porous electrodes, (2) hydrophilic versus hydrophobic membranes, and (3) conductive versus non‐conductive membranes in their ability to cause capillary wetting‐induced corrosion of metal fasteners. We proposed a simple solution for the problem: separating the metal fasteners from the porous membrane electrode with a non‐porous conductive graphite foil, which keeps the electrochemical circuit open. We have validated this solution and propose it as a standard method for experiments using porous electrodes and electrically conductive membranes. [ABSTRACT FROM AUTHOR]

AbstractLearning to read Chinese characters poses a considerable challenge for children, particularly those with dyslexia. We designed a tangible system, named Character Alive, to assist children aged 5 to 7 in mastering Chinese radicals and characters. The system employs animations and color cues to clarify the concepts of radicals and morphemes. It also incorporates physical radical cards that work in synergy with an artificial intelligence module to facilitate stroke tracing and character composition. We conducted a two-week within-group study involving 20 six-year-old children who used both our tangible system and an equivalent multitouch version to learn Chinese radicals and characters. The results showed that both systems significantly improved the children’s accuracy in character reading and composition. However, our tangible design outperformed the multitouch variant by increasing children’s learning motivation, enabling hands-on actions, and promoting a diverse range of beneficial learning strategies. We discuss the design implications for creating effective tangible systems to facilitate Chinese language acquisition among children. [ABSTRACT FROM AUTHOR]

A cyclic trinuclear complex is synthesized from AgI and 1H-pyrazole-4-carbaldehyde. Reticulation of the complex with 1,3,5-tris(4-aminophenyl)benzene through Schiff-base reaction affords a porous FDM-72 framework. Amine choice is systematically investigated as it may initiate metal reduction. This study proposes a new route and its amine selection criterion to synthesize Ag-based frameworks. [ABSTRACT FROM AUTHOR]

The precise control of the regioselectivity in the transition metal‐catalyzed migratory hydrofunctionalization of alkenes remains a big challenge. With a transient ketimine directing group, the nickel‐catalyzed migratory β‐selective hydroarylation and hydroalkenylation of alkenyl ketones has been realized with aryl boronic acids using alkyl halide as the mild hydride source for the first time. The key to this success is the use of a diphosphine ligand, which is capable of the generation of a Ni(II)‐H species in the presence of alkyl bromide, and enabling the efficient migratory insertion of alkene into Ni(II)‐H species and the sequent rapid chain walking process. The present approach diminishes organosilanes reductant, tolerates a wide array of complex functionalities with excellent regioselective control. Moreover, this catalytic system could also be applied to the migratory hydroarylation of alkenyl azahetereoarenes, thus providing a general approach for the preparation of 1,2‐aryl heteroaryl motifs with wide potential applications in pharmaceutical discovery. [ABSTRACT FROM AUTHOR]

Predator–prey interaction has long been an interesting item in the research of animal behaviors. Given that live prey can damage their predators, predators must trade foraging efficiency for safety while hunting, but the extent of this trade‐off is not yet clear. Tiger beetles display diversity in their diets and hunting strategies, and hence, they become an ideal system to address how self‐security affects foraging efficiency. We addressed this question in captive adult tiger beetles Cicindela gemmata. By offering several types of arthropod and plant foods, we confirmed that C. gemmata is carnivorous. We found that C. gemmata hunt by either ambushing or chasing their prey, and that they switch between strategies based on differences in the number of prey, the prey status and encounter rate, and the number of predators. Ambushing success increased with the number of prey but decreased with prey encounter rate. Chasing success decreased as prey body size and encounter rate increased. Foraging Cicindela gemmata often gave up an attack when it was nonfatal. This active giving up of hunting may be a consequence of a trade‐off between foraging efficiency and self‐security. Therefore, it is an adaptive response to the risk of injury when hunting for larger live prey. [ABSTRACT FROM AUTHOR]

Increasingly, non-pharmacological interventions are being identified and applied to post-stroke dysphagia. Nevertheless, there is insufficient evidence to assess which type of interventions are more effective. In this study, the randomized controlled trials of non-pharmacological interventions on post-stroke dysphagia were retrieved from the relevant databases. Including 96 studies and 12 non-drug treatments. Then, and the network meta-analysis is carried out by statistical software. The results show: In the aspects of videofluoroscopic swallowing study (VFSS), Standardized Swallowing Assessment (SSA), swallowing-quality of life (SWAL-QOL), Water swallow test (WST); Acupuncture + electrotherapy + rehabilitation training, acupuncture + rehabilitation training + massage, electrotherapy + rehabilitation training, acupuncture + electrotherapy + rehabilitation training, electrotherapy, acupuncture + rehabilitation training + acupoints sticking application have significant effects in post-stroke dysphagia. Compared with other interventions, they have more advantages in improving the above indicators. A substantial number of high-quality randomized clinical trials are still necessary in the prospective to validate the therapeutic effectiveness of non-pharmacological interventions in post-stroke dysphagia and the results of this Bayesian network meta-analysis. [ABSTRACT FROM AUTHOR]