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Fabricating efficient non‐platinum‐group‐metal catalysts for the oxygen reduction reaction (ORR) in proton‐exchange membrane fuel cells still remains a big challenge. This study creates a unique bamboo‐like architecture of Mn and Fe single atomic sites (SASs) anchored on core‐shell structure of nanopaticles@carbon nanotubes (MnFe SASs/NPs@CNTs) via a precursor route, where the Fe nanoparticles (NPs) (identified as γ‐Fe and Austenite) are confined into CNTs, such an architecture exhibits compelling ORR activity and durability in 0.1 m HClO4. Experiments and calculations both reveal that the electron donor–acceptor paradigm between Mn SASs and Fe NPs launches a lattice‐electron coupling mechanism not only increasing occupation of π‐antibonding orbital in Mn−*O intermediates but also rising Jahn–Teller effect, thereby destabilize the Mn−*O intermediate and eventually facilitate the potential‐limiting step from *O to *OH. Such a coupling activation of the ORR‐inert Mn SASs greatly improves ORR performances of MnFe SASs/NPs@CNTs. [ABSTRACT FROM AUTHOR]

Recently, Ni-rich LiNixCoyMn1−x−yO2 (x ≥ 0.8) draw significant research attention as cathode materials in lithium-ion batteries due to their superiority in energy density. However, the oxygen release and the transition metals (TMs) dissolution during the (dis)charging process lead to serious safety issues and capacity loss, which highly prevent its application. In this work, we systematically explored the stability of lattice oxygen and TM sites in LiNi0.8Co0.1Mn0.1O2(NCM811) cathode via investigating various vacancy formations during lithiation/delithiation, and properties such as the number of unpaired spins (NUS), net charges, and d band center were comprehensively studied. In the process of delithiation (x = 1 → 0.75 → 0), the vacancy formation energy of lattice oxygen [Evac(O)] has been identified to follow the order of Evac(O–Mn) > Evac(O–Co) > Evac(O–Ni), and Evac(TMs) shows a consistent trend with the sequence of Evac(Mn) > Evac(Co) > Evac(Ni), demonstrating the importance of Mn to stabilize the structural skeleton. Furthermore, the |NUS| and net charge are proved to be good descriptors for measuring Evac(O/TMs), which show linear correlations with Evac(O) and Evac(TMs), respectively. Li vacancy plays a pivotal role on Evac(O/TMs). Evac(O/TMs) at x = 0.75 vary extremely between the NiCoMnO layer (NCM layer) and the NiO layer (Ni layer), which correlates well with |NUS| and net charge in the NCM layer but aggregates in a small region in the Ni layer due to the effect of Li vacancies. In general, this work provides an in-depth understanding of the instability of lattice oxygen and transition metal sites on the (104) surface of Ni-rich NCM811, which might give new insights into oxygen release and transition metal dissolution in this system. [ABSTRACT FROM AUTHOR]

Rechargeable Na‐CO2 batteries are considered to be an effective way to address the energy crisis and greenhouse effect due to their dual functions of CO2 fixation/utilization and energy storage. However, the insolubility and irreversibility of solid discharge products lead to poor discharge capacity and poor cycle performance. Herein, a novel strategy is proposed to enhance the electrochemical performance of hybrid Na‐CO2 batteries, using water‐in‐salt electrolyte (WiSE) to establish an optimal reaction environment, regulate the CO2 reduction pathway, and ultimately convert the discharge product of the battery from Na2CO3 to formic acid (HCOOH). This strategy effectively resolves the issue of poor reversibility, allowing the battery to exhibit excellent cycle performance (over 1200 cycles at 30 °C), especially under low‐temperature conditions (2534 cycles at −20 °C). Furthermore, density functional theory (DFT) calculations and experiments indicate that by adjusting the relative concentration of H/O atoms at the electrolyte/catalyst interface, the CO2 reduction pathway in the battery can be regulated, thus effectively enhancing CO2 capture capability and consequently achieving an ultra‐high discharge specific capacity of 148.1 mAh cm−2. This work effectively promotes the practical application of hybrid Na‐CO2 batteries and shall provide a guidance for converting CO2 into products with high‐value‐added chemicals. [ABSTRACT FROM AUTHOR]

Development of advanced sensing systems capable of trace analysis for small biomolecules is promising yet challenging in both physiological and pathological fields. Nanostructures with a specific surface where the reaction process happens directly govern the overall sensing performance because of the facet-dependent effects on the atomic level. Using core–shelled Au@Pd bimetallic nanorods as the platform, we herein studied the impacts of surface atomic arrangement on the performance of electrochemical H2O2 biosensing. Specifically, Au@Pd with a (100)-facet (Au@Pd-100) exhibited more than 3 times higher sensitivities than Au@Pd with a (111)-facet in H2O2 detection. Based on the theoretical calculations, this strong facet-dependence was attributed to the efficient charge transfer from Au core to Pd (100) shell and favorable intermediate adsorption energy over (100)-facet. The Au@Pd-100 exhibited great H2O2 sensing performance with high sensitivity (up to 383.0 μA mM–1 cm–2ECSA), relatively low detection limit (∼1.0 μM) and wide applicable detection range (1.0 to 1.75 × 103 μM), which also ensured the high efficiency of Au@Pd-100 sensor in real-time monitoring of H2O2 released from the cancer cells. In depth interpretation of facet-dependent effect in this work not only highlights the significant role of the surface engineering in performance improvement but also can offer guidelines for the fabrication of efficient biosensors. [ABSTRACT FROM AUTHOR]

This paper examines the community-based ecotourism on Yim Tin Tsai which is a representative example of Hong Kong’s responsible management. The island presents a local community of the explored saltpan and natural resources. The research draws upon criticism of ecotourism in Yim Tin Tsai as a way of understanding the importance of balancing nature with the economic interests. As adopting a qualitative research method for the case study, the experience and thoughts reflected by the local resident of will be also analyzed.

Background: Insulin resistance (IR) in hepatocytes endangers human health, and frequently results in the development of non-alcoholic fatty liver disease (NAFLD). Research on m6A methylation of RNA molecules has gained popularity in recent years; however, the molecular mechanisms regulating the processes of m6A modification and IR are not known. The cytochrome P450 (CYP450) enzyme system, which is mainly found in the liver, is associated with the pathogenesis of NAFLD. However, few studies have been conducted on CYP450 related m6A methylation. Here, we investigated the role of the methyltransferase METTL3 in exacerbating IR in hepatocytes, mainly focusing on the regulation of m6A modifications in CYP2B6. Methods and results: Analysis using dot blot and epitranscriptomic chips revealed that the m6A modification pattern of the transcriptome in high-fat diet (HFD)-induced fatty liver and free fatty acid (FFA)-induced fatty hepatocytes showed significant changes. CYP450 family members, especially Cyp2b10, whose homolog in humans is CYP2B6, led to a noticeable increase in m6A levels in HFD-induced mice livers. Application of the METTL3 methyltransferase inhibitor, STM2457, increased the level of insulin sensitivity in hepatocytes. We then analyzed the role of METTL3 in regulating m6A modification of CYP2B6 in hepatocytes. METTL3 regulated the m6A modification of CYP2B6, and a positive correlation was found between the levels of CYP2B6 translation and m6A modifications. Furthermore, interference with METTL3 expression and exposure to STM2457 inhibited METTL3 activity, which in turn interfered with the phosphorylated insulin receptor substrate (pIRS)-glucose transporter 2 (GLUT2) insulin signaling pathway; overexpression of CYP2B6 hindered IRS phosphorylation and translocation of GLUT2 to membranes, which ultimately exacerbated IR. Conclusion: These findings offer unique insights into the role that METTL3-mediated m6A modifications of CYP2B6 play in regulating insulin sensitivity in hepatocytes and provide key information for the development of strategies to induce m6A modifications for the clinical treatment of NAFLD. [ABSTRACT FROM AUTHOR]

Carbon monoxide electroreduction (COER) has been a key part of tandem electrolysis of carbon dioxide (CO2), in which searching for high catalytic performance COER electrocatalysts remains a great challenge. Herein, by means of density functional theory (DFT) computations, we explored the potential of a series of transition metal atoms anchored on N-doped γ-graphyne (TM@N-GY, TM from Ti to Au) as the COER electrocatalysts. We found that the final product selectivity of these single-atom catalysts depended on the position of the metal atom in the periodic table, with metals in the front and middle of each periodic period exhibiting high selectivity for CH4, while metals in the back producing CH3OH. Machine learning (ML) found that metal atomic number was intrinsic to the difference in COER performance of these single-atom catalysts (SACs). The free energy changes showed that Mn@N-GY and Ni@N-GY exhibited outstanding COER catalytic performance for producing CH4 and CH3OH, respectively. Our results provide theoretical and experimental guidance for designing efficient COER catalysts to generate C1 products. [ABSTRACT FROM AUTHOR]

Event-related potentials (ERPs) were utilized in an investigation of 21 six-month-olds' attention to and processing of global and local properties of hierarchical patterns. Overall, infants demonstrated an advantage for processing the overall configuration (i.e., global properties) of local features of hierarchical patterns; however, processing advantages were found to vary based on individual differences in look duration. Short-looking infants showed differences in the negative central ERP component and the late slow wave (LSW) indicating greater attention to and discrimination of changes in global properties. Analysis of the LSW revealed that long-looking infants discriminated changes in local features, but did not discriminate changes in global properties of visual stimuli. These findings indicate that short- and long-looking infants utilize different approaches when processing hierarchical patterns. (Contains 5 figures.)

Past studies have identified individual differences in infant visual attention based upon peak look duration during initial exposure to a stimulus. Colombo and colleagues found that infants that demonstrate brief visual fixations (i.e., short lookers) during familiarization are more likely to demonstrate evidence of recognition memory during subsequent stimulus exposure than infants that demonstrate long visual fixations (i.e., long lookers). This study utilized event-related potentials (ERPs) to examine possible neural mechanisms associated with individual differences in visual attention and recognition memory for 6- and 7.5-month-old infants. Short- and long-looking infants viewed images of familiar and novel objects during ERP testing. There was a stimulus type by looker type interaction at temporal and frontal electrodes on the late slow wave (LSW). Short lookers demonstrated an LSW that was significantly greater in amplitude in response to novel stimulus presentations. No significant differences in LSW amplitude were found based on stimulus type for long lookers. These results indicate deeper processing and recognition memory of the familiar stimulus for short lookers. (Contains 3 figures, 1 table, and 3 footnotes.)

High‐performance rechargeable Zn‐air batteries with long‐life stability are desirable for power applications in electric vehicles. The key component of the Zn‐air batteries is the bifunctional oxygen electrocatalyst, however, designing a bifunctional oxygen electrocatalyst with high intrinsic reversibility and durability is a challenge. Through density functional theory calculations, it is found that the catalytic activity originated from the electronic and geometric coordination structures synergistic effect of the Fe and Co dual‐sites with metal‐N4 coordination environment, assisting the stronger hybridization of electronic orbitals between Co (dxz, dz2) and OO* (px, pz), thus making the stronger O2 active ability of Co active site. These findings enable to development of a fancy dual single‐atom catalyst comprising adjacent FeN4 and CoN4 sites on N‐doped carbon matrix (FeCo‐NC). FeCo‐NC exhibits extraordinary bifunctional activities for oxygen reduction and evolution reaction (ORR/OER), which displays high half‐wave potential (0.893 V) for the ORR, and low overpotential (343 mV) at 10 mA cm−2 for the OER. The assembled FeCo‐NC air‐electrode works well in the flexible solid‐state Zn‐air battery with a high specific capacity of 747.0 mAh g−1, a long‐time stability of more than 400 h (30 °C), and also a superior performance at extreme temperatures (−30 °C–60 °C). [ABSTRACT FROM AUTHOR]