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【Objective】 The ecological functions of a river are manifold; and how to determine river flow rates which are ecologically sustainable is important but not trivial. In this paper, we proposed a new approach to model river habitat. 【Method】 The model is based on multiple indicator species and considers their competition as well as the consequence for growth of individual species. The model is constructed based on the fuzzy logic method to establish the quantitative relationship between river habitat quality and runoff conditions. We applied the model to the Xinyang section of the Shihe River. 【Result】 The sustainable ecological water flow in this section of the river calculated by the model is 160~260 m3/s, and the minimum ecological flow rate is 60 m3/s. The result interval is stricter than that calculated from the single indicator species model using crucian carp as the indicator. 【Conclusion】 Multiple indicator species model we proposed for determining ecologically sustainable river flow is robust and accurate. It can be used for designing sustainable development and utilization of river water resources.

Exploring non-precious oxygen reduction reaction (ORR) catalysts is essential to fuel cells and seawater metal–air batteries. Transition metal nitrides are promising ORR catalysts with high corrosion resistance but fail to render satisfactory ORR performance. Herein, we introduce a novel method for the synthesis of carbon nanosheet-supported transition metal nitrides. Using dicyandiamine (DCDA) as the nitrogen and carbon source, we prepared carbon nanosheet-supported CrN nanoparticles (CrN/CNS) via a two-step pyrolysis method. The optimal CrN/CNS material has an ORR half-wave potential (E1/2) of 0.76 V vs. reversible hydrogen electrode (RHE) in acidic media and 0.50 V vs. RHE in simulated seawater, which is one of the best among those reported for transition metal nitrides. Furthermore, the optimal material has remarkable ORR stability in both acidic media and simulated seawater. Its ORR E1/2 shows 27 mV decay in acidic media and 20 mV increase in simulated seawater after stability tests, outperforming a commercial Pt/C catalyst and many transition metal nitrides. More importantly, the optimal CrN/CNS material-based seawater Zn–air batteries (ZABs) exhibit good stability within 200 h constant discharging. It is found that both the proportion of the Cr–N valence state and the Cr content in surfaces played a key role in the ORR activity of CrN/CNS materials. [ABSTRACT FROM AUTHOR]

Although anion exchange membrane water electrolyzer (AEMWE) is an emerging device in the green hydrogen production industry, the use of alkaline electrolyte tackles the practicality due to the issues of lowering system efficiency and environmental impacts. State‐of‐the‐art technology using pure water as an electrolyte is advancing to overcome the current challenges of AEMWE. In particular, the development of this technology requires a comprehensive evaluation of techno‐economic aspects, aiming to balance innovation with cost considerations. This involves the critical development of advanced catalysts, membranes, and devices designed for efficiency, as well as assessing their economic viability amidst prevailing technological challenges. This review delves into the timely technical challenges of developing pure water‐fed AEMWE, highlights current progress and research prospects, and suggests opportunities for advancing AEMWE technology. This review also emphasizes the importance of advanced characterization techniques for effective analysis and evaluation in this context. [ABSTRACT FROM AUTHOR]

In the electrocatalytic CO2 reduction reaction (CO2RR), metal catalysts with an oxidation state generally demonstrate more favorable catalytic activity and selectivity than their corresponding metallic counterparts. However, the persistence of oxidative metal sites under reductive potentials is challenging since the transition to metallic states inevitably leads to catalytic degradation. Herein, a thorough review of research on oxidation-state stabilization in the CO2RR is presented, starting from fundamental concepts and highlighting the importance of oxidation state stabilization while revealing the relevance of dynamic oxidation states in product distribution. Subsequently, the functional mechanisms of various oxidation-state protection strategies are explained in detail, and in situ detection techniques are discussed. Finally, the prevailing and prospective challenges associated with oxidation-state protection research are discussed, identifying innovative opportunities for mechanistic insights, technology upgrades, and industrial platforms to enable the commercialization of the CO2RR. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate the role and mechanism of microRNA-204-5p (miR-204-5p) in atherosclerosis (AS)-related abnormal human vascular smooth muscle cells (hVSMCs) function. Firstly, we analyzed the expression of miR-204-5p and found that the miR-204-5p expression level was clearly downregulated in atherosclerotic plaque tissues and blood samples compared to the normal controls. Then, matrix metallopeptidase-9 (MMP-9) was predicted to be the potential target of miR-204-5p by TargetScan and this prediction was confirmed by luciferase assays. Besides, we observed that miR-204-5p could negatively regulate the expression of MMP-9 in hVSMCs. Subsequently, Thiazolyl Blue Tetrazolium Bromide (MTT) assay, transwell assay and flow cytometry were performed to detect the proliferation, migration and apoptosis of hVSMCs. Down-expression of miR-204-5p led to the promotion of proliferation and migration accompanied with the suppression of apoptosis in hVSMCs, and these effects were reversed by MMP-9-siRNA. In addition, overexpressed miR-204-5p could inhibit hVSMC proliferation and migration and promote the apoptosis of hVSMCs. However, the effects were also abrogated by overexpressed MMP-9. Together, our findings showed that miR-204-5p plays an important role in the growth and migration of hVSMCs by targeting MMP-9, which might be a novel biomarker and promising therapeutic target for AS.

Comprehensive Summary: Seawater electrolysis holds great promise for hydrogen production in the future, while the development of anodic catalysts has been severely hampered by the side‐reaction, chloride evolution reaction. In this work, nano‐flower‐cluster structured CoO@FeSe2/CF catalysts are synthesized via a scalable electrodeposition technique, and the performance is systematically studied. The oxygen evolution reaction (OER) overpotential of CoO@FeSe2/CF is 267 mV at 100 mA·cm−2, which is significantly lower than that of the IrO2 catalyst (435 mV). Additionally, the catalyst shows high selectivity for OER (97.9%) and almost no loss of activity after a durability test for 1100 h. The impressive performance is attributed to the dense rod‐like structure with abundant active centers after electrochemical activation and the in‐situ generated CoOOH and FeOOH that improve the catalytic activity of the catalyst. The synergistic effect induced by the non‐uniform structure endows the catalyst with excellent stability. [ABSTRACT FROM AUTHOR]

Electrochemical structural reconstruction of catalysts may generate real active sites that differ from the initial catalyst, but is often ignored. Herein, combining in situ and ex situ techniques, it is identified that the bismuth nanosheets (NS) dotted with large numbers of coordinatively unsaturated pit sites is produced via the in situ structural reconstruction of Bi(OH)3 NS. Such reconstructed Bi NS shows greatly improved catalytic activity toward CO2 electroreduction, with a 2.6‐fold increase in current density compared with intact Bi NS, high Faradaic efficiency for HCOO− production (>95%), and an extraordinary turnover frequency of 0.35 s−1 at −0.98 VRHE. In addition, it delivers industrial‐relevant current density of 325 mA cm−2 without compromising selectivity in a flow cell. The mechanistic studies demonstrate that these coordinatively unsaturated sites acting as the real active sites favor the stabilization of key intermediate *OCHO, which thus facilitate the reaction kinetics for HCOO− production. This work not only provides a unique perspective on the construction of efficient catalysts for CO2 electroreduction, but also implies the importance in recognition of structural reconstruction. [ABSTRACT FROM AUTHOR]

Modulating the local coordination structure of metal single-atom catalysts (SACs) is extensively employed to tune the catalytic activity, but rarely involved in regulating the reaction pathway which fundamentally determines the product selectivity. Herein, we report that the product selectivity of electrochemical CO2 reduction (CO2RR) on the single-atom indium-NxC4−x (1 ≤ x ≤ 4) catalysts could be tuned from formate to CO by varying the carbon and nitrogen occupations in the first coordination sphere. Surprisingly, the optimal In SAC showed great promise for CO production with the maximum Faradic efficiency of 97%, greatly different from the reported In-based catalysts where the formate is the dominant product. Combined experimental verifications and theoretical simulations reveal that the selectivity switch from formate to CO on In SACs originates from active sites shift from indium center to the indium-adjacent carbon atom, where the indium site favors formate formation and the indium-adjacent carbon site prefers the CO pathway. The present work suggests the active sites in metal SACs may shift from the widely accepted metal center to surrounding carbon atoms, thereby offering a new implication to revisit the active sites for metal SACs. [ABSTRACT FROM AUTHOR]

Advancing the development of electrocatalytic CO2 reduction reaction (CO2RR) to address the environmental issues caused by excessive consumption of fossil fuels requires rational design of remarkable electrocatalysts, where the identification of active sites and further understanding of structure–performance relationship are the bases. However, the notable dynamic evolution often appears on the catalysts, with typical examples of Cu‐based catalysts, under operating conditions, causing great difficulty in identifying the real active sites and further understanding the correlations between structure and catalytic property. In this context, understanding the dynamic evolution process of catalytically active sites during CO2RR is of particular importance, which inspires to organize the present review. Herein, the fundamental principles of dynamic evolution in CO2RR including thermodynamics and kinetics aspects, followed by the introduction of operando techniques employed to probe the evolution under operating conditions are first highlighted. The dynamic evolution behaviors, involving atomic rearrangement and change in chemical state, on typical catalysts are further discussed, with emphasis on the correlations between evolution behaviors and catalytic properties (activity, selectivity, and stability). The emerging CO2 pulsed electrolysis technique that behaves promise to manipulate the dynamic evolution and future opportunities are finally discussed. [ABSTRACT FROM AUTHOR]

The lack of highly efficient catalysts severely hinders large‐scale application of electrochemical hydrogen evolution reaction (HER) for hydrogen production from water. Herein, synergistic cascade hydrogen evolution boosting by combining the strategies of carbon layer confinement and surface oxophilicity modification is realized. The carbon layers confined ultrafine RuCr nanoparticles (RuCr@C) exhibit outstanding HER activity (j10= 19 mV, turnover frequency = 4.25 H2 s‐1), surpassing the benchmark Pt/C and most of the reported HER catalysts. Combined experimental verifications and theoretical simulations reveal that surface adsorption modification and electronic structure regulation synergistically boosts the HER kinetics over the RuCr@C catalyst. The Volmer step is accelerated by stabilizing the final state of water dissociation (*H and *OH) through Cr doping, and the Heyrovsky step is promoted via carbon layers confinement. As such, this work highlights a synergistic cascade strategy to boost HER kinetics which is of fundamental importance to accelerate future advances in electrocatalysis. [ABSTRACT FROM AUTHOR]

Characterized by long‐range atomic ordering, well‐defined stoichiometry, and controlled crystal structure, intermetallics have attracted increasing attention in the area of chemical synthesis and catalytic applications. Liquid‐phase synthesis of intermetallics has arisen as the promising methodology due to its precise control over size, shape, and resistance toward sintering compared with the traditional metallurgy. This short review tends to provide perspectives on the liquid‐phase synthesis of intermetallics in terms of both thermodynamics and methodology, as well as its applications in various catalytic reactions. Specifically, basic thermodynamics and kinetics in the synthesis of intermetallics will be first discussed, followed by discussing the main factors that will affect the formation of intermetallics during synthesis. The application of intermetallics in electrocatalysis will be demonstrated case by case at last. We conclude the review with perspectives on the future developments with respect to both synthesis and catalytic applications. [ABSTRACT FROM AUTHOR]

Electrochemical energy conversion devices, with typical examples of fuel cells, are the centers in building a sustainable energy system that avoids environmental pollution and lowers the dependence on fossil fuels. Platinum (Pt)‐based catalysts are among the most potential candidates to drive these reactions due to their superior catalytic performance. Among the various Pt‐based catalysts, Pt‐based ultrathin nanowires exhibit remarkable catalytic performance due to the unique structural merits (i.e., high Pt atom utilization and strong interaction with supports). In this review, we attempt to summarize the recent advances in the synthesis of Pt‐based ultrathin nanowires, as well as their applications in various kinds of electrocatalytic reactions. We conclude this review with an emphasis on the current challenges in terms of synthesis and applications of Pt‐based ultrathin nanowires. Perspectives on further development are also proposed, which is expected to guide the related research in the future. [ABSTRACT FROM AUTHOR]

Atomically ordered intermetallic nanoparticles exhibit improved catalytic activity and durability relative to random alloy counterparts. However, conventional methods with time‐consuming and high‐temperature syntheses only have rudimentary capability in controlling the structure of intermetallic nanoparticles, hindering advances of intermetallic nanocatalysts. We report a template‐directed strategy for rapid synthesis of Pd‐based (PdM, M=Pb, Sn and Cd) ultrathin porous intermetallic nanosheets (UPINs) with tunable sizes. This strategy uses preformed seeds, which act as the template to control the deposition of foreign atoms and the subsequent interatomic diffusion. Using the oxygen reduction reaction (ORR) as a model reaction, the as‐synthesized Pd3Pb UPINs exhibit superior activity, durability, and methanol tolerance. The favored geometrical structure and interatomic interaction between Pd and Pb in Pd3Pb UPINs are concluded to account for the enhanced ORR performance. [ABSTRACT FROM AUTHOR]

Electrochemical energy conversion devices, with typical examples of fuel cells, are the centers in building a sustainable energy system that avoids environmental pollution and lowers the dependence on fossil fuels. Platinum (Pt)‐based catalysts are among the most potential candidates to drive these reactions due to their superior catalytic performance. Among the various Pt‐based catalysts, Pt‐based ultrathin nanowires exhibit remarkable catalytic performance due to the unique structural merits (i.e., high Pt atom utilization and strong interaction with supports). In this review, we attempt to summarize the recent advances in the synthesis of Pt‐based ultrathin nanowires, as well as their applications in various kinds of electrocatalytic reactions. We conclude this review with an emphasis on the current challenges in terms of synthesis and applications of Pt‐based ultrathin nanowires. Perspectives on further development are also proposed, which is expected to guide the related research in the future. [ABSTRACT FROM AUTHOR]

Electrochemical reduction of carbon dioxide (CO2ER) has attracted enormous research interest owing to the feasibility to consume the excessive CO2 in atmosphere arising from overconsumption of fossil fuels and store the chemical energy in value‐added chemicals. The conversion of CO2 into methane (CH4) is of great importance, and recent advance has allowed the design and utilisation of effective electrocatalysts with improved electrocatalytic performance regarding product selectivity and Faradaic efficiency. In this mini‐review, we discuss the recent progress and challenges of metal‐based heterogeneous electrocatalyst for CO2ER into CH4 by starting with fundamental mechanisms and designing principles of effective electrocatalysts. In the following sections, we present several successful demonstrations and analyze the effect and contribution arising from their chemical composition, facet, size, and other characters. Some challenges and promising strategies are discussed finally. [ABSTRACT FROM AUTHOR]

Effective valorisation of biomass into value-added chemicals represents a promising strategy to reduce the reliance on fossil fuel energy, and 5-hydroxymethylfurfural (HMF) has been identified as a critical and versatile platform chemical among many biomass-derived intermediates. Electro-catalytic HMF oxidation into 2,5-furandicarboxylic acid (FDCA), a key monomer for biobased polymers, in an ecofriendly and cost-effective manner has recently emerged as a promising solution compared with conventional thermo-catalytic strategy that relies on high pressure O2 and elevated temperatures. Herein, ultrathin Ni(OH)2 nanosheets decorated with amorphous Cu(OH)2 islands are identified to be a highly efficient catalyst for the selective electrooxidation of HMF. Long-term chronoamperometry demonstrates a high faradaic efficiency of 91.2% towards FDCA production, and the HMF oxidation is determined to proceed follow a DFF pathway. Nickel species are proposed to be the active sites for HMF oxidation, while amorphous copper hydroxide functions to strengthen the affinity for reaction intermediates and modulate the electronic structure of Ni, leading to an earlier onset for HMF oxidation. The catalyst design strategy proposed in this work has shown great potential in improving HMF electrooxidation efficiency, which is essential for the widespread application of HMF electrooxidation. [ABSTRACT FROM AUTHOR]

Electrocatalytic energy conversion is one of the most promising pathways to develop clean and renewable energy technologies, and the development of high‐performance electrocatalysts to improve the energy conversion efficiency is of paramount importance. Metal nanocrystals with twin defects possess unique features, including lattice strain and high density of low‐coordinated atoms at the twin boundary, endowing them with excellent catalytic performance in various electrocatalytic reactions. Herein, we briefly summarize recent advances in the synthesis of metal nanocrystals with various twin structures, recent breakthroughs related to electrocatalytic applications of twin metal nanocrystals are also overviewed. Finally, the major challenges and perspectives for future development of twin metal nanocrystals in electrochemical applications are proposed. [ABSTRACT FROM AUTHOR]

Psoriasis is a chronic autoimmune disease. Identification of the biomarkers responsible for Traditional Chinese Medicine (TCM) syndromes of psoriasis can help researchers recognize the different aspects of psoriasis and find novel therapeutic targets for the treatment of psoriasis. The current study investigated the levels of circulating Mo-MDSCs and Mo-MDSC-associated immune factors in the peripheral blood of psoriasis patients with different TCM syndromes. We found that the frequency of Mo-MDSCs (CD14+HLA-DR−/low cells) among CD14+ cells from plaque psoriasis patients with blood-stasis (BS) syndrome was significantly increased when compared with healthy controls p < 0.001 and blood-heat (BH) syndrome group p < 0.001 , respectively. However, serum IL-2, IL-4, IL-6, IL-10, IL-17A, TNF-α, IFN-γ, iNOS, Arg-1, and NO concentration showed no statistically significant difference between healthy controls and psoriasis patients as well as no significant difference between the BH and BS syndrome groups. Compared with healthy controls, the mRNA expression of Arg-1, TNF-α, ROR-γ, and PD-L1 was increased, while the mRNA expression of PD-1 and IL-10 was decreased in PBMCs from psoriasis patients. Moreover, the mRNA expression of TNF-α and FOXP3 in PBMCs showed a pronounced statistical difference between the psoriatic BH syndrome group and the BS syndrome group. Therefore, we provide evidence that the percentage of CD14+HLA-DR−/low MDSC/ CD14+ cells and TNF-α and Foxp3 mRNA expression levels in PBMCs are potential biomarkers for distinguishing TCM BH syndrome and BS syndrome. [ABSTRACT FROM AUTHOR]

We have developed a facile one-step hydrothermal strategy to synthesize pyramid-like NiSe2 nanostructures, serving as electrode materials for battery-supercapacitor hybrid (BSH) devices. The NiSe2 nanopyramid electrode exhibits superior electrochemical performances, including a high specific capacity of 240.83 mAh g−1 at current density of 1 A g−1 and a low internal resistance of 0.85 Ω. The all-solid-state hybrid devices have been assembled with NiSe2 as the battery-type electrode and activated carbon as the capacitor-type electrode. The hybrid device exhibits a high energy density of 0.196 mWh cm−2 at power density of 1.60 mW cm−2. The internal resistance of 1.52 Ω further reveals the nature of low resistance and high conductivity for the hybrid devices. Connecting two hybrid devices in series is able to drive a red LED for more than 3 min after charging for 9 s. This work has demonstrated that the pyramid-like NiSe2 nanostructure is expected to be an ideal high specific capacity electrode for BSH devices, especially for all-solid-state energy storage devices and portable electronic devices. [ABSTRACT FROM AUTHOR]