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The compositing strategy offers great potential in designing bifunctional oxygen electrocatalysts for Zn–air batteries. Recent reports reveal that the couple of RuO2, serving as a benchmark oxygen evolution reaction (OER) catalyst, with other oxygen reduction reaction (ORR) catalysts is a wise choice to build highly efficient bifunctional electrocatalysts. However, the design criteria for ORR and OER activities of RuO2‐based composite catalysts are still unclear. Herein, a series of transition metal (Fe, Co, Mn, and Ni)‐doped spinel oxides are designed to support RuO2 nanorods for exploring the reaction mechanism. Through advanced technology, it is considered that increasing the content and binding energy of Co3+ and enhancing the oxidation state of Ru4+ is an efficient strategy to promote ORR and OER activities for RuO2/Co‐based spinel oxide composite catalysts. It is found that coupling Mn‐doping Co3O4 (CMO) supports with RuO2 can induce the highest catalytic activities in ORR/OER and excellent performance in rechargeable Zn–air batteries. Operando electrochemical impedance spectroscopy and theoretical calculation further prove the synergistic effect between RuO2 and CMO supports originated from the oxygen overflow to overcome the large barrier for oxygen desorption on RuO2 during OER and oxygen adsorption on CMO supports during ORR. [ABSTRACT FROM AUTHOR]

Immunoglobulin γ-1 heavy chain constant region (IGHG1) is a functional isoform of immunoglobulins and plays an important role in the cytolytic activity of immune effector cells. Dysregulated IGHG1 was implicated in the occurrence and development of various tumors. Protoporphyrin IX (PpIX) is an endogenous fluorophore and is used in photodynamic therapy, which induces the generation of reactive oxygen species to initiate the death of tumor cells. However, the roles of IGHG1 in the colorectal cancer cell proliferation and PpIX accumulation have not been reported yet. Data from qRT-PCR and western blot analysis showed that IGHG1 was up-regulated in the colorectal cancer cells. Colorectal cancer cells were then transfected with shRNA targeting IGHG1 to down-regulate IGHG1 and conducted with Cell Counting Kit 8 (CCK8) and colony formation assays. Results demonstrated that shRNA-mediated down-regulation of IGHG1 decreased cell viability of colorectal cancer and suppressed cell proliferation. Moreover, PpIX accumulation was promoted and the hemin content was decreased by the silence of IGHG1. Interference of IGHG1 reduced the phosphorylated extracellular signal-regulated kinase (ERK) and ferrochelatase (FECH) expression, resulting in retarded cell proliferation in an MEK-FECH axis-dependent pathway.

The method aims to recognize and extract the characteristic parameters of bridge cracks based on images of the cracks obtained through the application of preprocessing technologies, such as graying, graphical enhancements, spatial filtering, gray-level threshold segmentation, etc.. The approach has been tested for accuracy to avoid the incorrect identification of chaff as a method error. The proposed method has proved to be rather accurate and effective in extracting information on cracks from the bridge image tests.

Summary: This study investigated the effect of 5 freeze–thaw cycles (freezing at −18°C for 12 h and then thawing at 4°C for approximately 12 h) on the meat quality, proximate composition, water distribution and microstructure of bovine rumen smooth muscle (BSM). As the number of freeze–thaw cycles increased, BSM pH, shear force, water content and protein content decreased by 3.06%, 35.50%, 14.49% and 21.11%, respectively, whereas BSM thawing loss, cooking loss, pressing loss, total aerobic count (TAC), ash content and fat content increased by 108.12%, 47.75%, 78.33%, 90.99%, 105% and 35.20%, respectively. The freeze–thaw cycles resulted in greater protein and lipid oxidation, as evidenced by a 36.46% reduction in the sulfhydryl content and a 209.06% and 338.46% increase in the carbonyl and malondialdehyde contents, respectively. Ice crystal formation disrupted the structural integrity of the muscle tissue. Low‐field nuclear magnetic resonance results showed that the freeze–thaw cycles prolonged the relaxation times (T2b, T21 and T22), indicating that immobile water shifted to free water, and consequently, free water mobility increased. After 3 freeze–thaw cycles, the decline in shear force slowed, the increase in thawing loss became accelerated, and the TAC approached the domain value (6 log colony‐forming units/g). Therefore, the number of freeze–thaw cycles of smooth muscle during transport, storage and distribution should be controlled to 3 or fewer. The current results provide a theoretical basis and data support for the further utilisation and culinary processing of smooth muscle. [ABSTRACT FROM AUTHOR]

The development of an air electrode that is flexible in physical property and highly active and durable at different geometric status for both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is of crucial importance for the rational design of flexible rechargeable Zn‐air batteries (ZABs). Considering their good elasticity, high conductivity, and superior thermal and chemical stability, carbon nanotubes have been widely used as a catalyst support in various electrocatalysts, while oxide or metal nanoparticles have been frequently deposited on the carbon nanotube substrate to perform as the active materials. Considering the poor contact between active materials and carbon nanotubes may introduce a challenge for long‐term operating stability, in particular in flexible devices, pure carbon electrocatalyst is highly appreciated. Herein, a free‐standing air electrode with cobalt nanoparticles encapsulated N‐codoped carbon nanotube arrays uniformly grown on the surface of carbon fiber cloth is developed by a two‐step in situ growth method. Such a carbon‐based electrode shows outstanding activity for both ORR and OER. The flexible ZAB with such air electrode shows superior flexibility and stability working under extreme bending conditions. Moreover, the polarization and round‐trip efficiency for the flexible battery is 0.67 V and 64.4% at 2 mA/cm2, respectively, even after being operated for 30 hours. This study provides a feasible way to design all carbon‐based free‐standing and flexible electrode and enlightens the electrode design for flexible energy conversion/storage devices. [ABSTRACT FROM AUTHOR]

The Li-metal anode plays a critical role in meeting the ever-growing demands for high-energy-density batteries. The rational design of an electrolyte to suppress dendrite formation is of great significance for the practical use of a Li-metal anode in rechargeable Li-metal batteries. In this work, by taking advantage of the lithiophilic polyacenequinone polymer filler, a novel polymer-filler-reinforced gel polymer electrolyte with the merits of high mechanical flexibility, high ionic conductivity, and superior dendrite-Li suppressing ability has been developed. When this gel polymer electrolyte is used in Li symmetrical cells, small and stable Li-plating/stripping overpotentials (∼25 mV) can be maintained over 700 hours. When equipped with a high-voltage cathode of LiNi0.6Co0.2Mn0.2O2 (NCM622) for Li-metal batteries, a high coulombic efficiency of about 99% can be retained after 100 repeated cycles. Such superiority is mainly ascribed to the smart lithiophilic carbonyl groups on the polyacenequinone polymer filler, which can guide uniform Li-ion flux at the Li electrode/electrolyte interface to fundamentally suppress Li dendrite growth during cycling. This work paves a way for designing dendrite-suppressed gel polymer electrolytes for Li-metal batteries and related energy conversion and storage devices. [ABSTRACT FROM AUTHOR]

Lithium–sulfur (Li–S) batteries are of great interest due to their high theoretical energy density and potentially low cost. However, two of the key issues hindering their commercialization are the polysulfide shuttling and Li-dendrite growth, which result in severe capacity decay and serious safety hazards. Herein, liquid-phase delaminated birnessite (HxMnO2+x) nanosheets along with graphene and carbon nanotubes are utilized for the first time to create an "electronegative" coating layer for Li–S batteries to suppress the polysulfide shuttling and Li-dendrite growth. The as-prepared coating layer enables stable cycling of the Li–S battery with a low capacity decay rate of 0.04% per cycle over 1000 cycles at 1C. In addition, a Li-symmetrical cell with the coating layer shows suppressed dendrite growth even after being cycled over 1000 hours at 1 mA cm−2. This excellent performance is ascribed, in part, to the synergistic effect of the chemical and electrostatic interactions among polysulfides, Li ions, and [MnO2+x]x− ions, resulting in a homogeneous Li-ion flux distribution and a mitigated polysulfide shuttling. The proposed concept of an "electronegative" bifunctional coating layer illustrates a simple and effective way to develop highly stable and safe Li–S batteries. [ABSTRACT FROM AUTHOR]

Cancer‐associated fibroblasts (CAFs) are a major cellular component in the tumor microenvironment and have been shown to exhibit protumorigenic effects in hepatocellular carcinoma (HCC). This study aimed to delve into the mechanisms underlying the tumor‐promoting effects of CAFs in HCC. Small RNA sequencing was conducted to screen differential expressed microRNAs in exosomes derived from CAFs and normal fibroblasts (NFs). The miR‐92a‐3p expression was then measured using reverse transcriptase quantitative real‐time PCR in CAFs, NFs, CAFs‐derived exosomes (CAFs‐Exo), and NF‐derived exosomes (NFs‐Exo). Compared to NFs or NF‐Exo, CAFs and CAFs‐Exo significantly promoted HCC cell proliferation, migration, and stemness. Additionally, compared to NFs or NF‐Exo, miR‐92a‐3p level was notably higher in CAFs and CAFs‐Exo, respectively. Exosomal miR‐92a‐3p was found to enhance HCC cell proliferation, migration, and stemness. Meanwhile, AXIN1 was targeted by miR‐92a‐3p. Exosomal miR‐92a‐3p could activate β‐catenin/CD44 signaling in HCC cells by inhibiting AXIN1 messenger RNA. Furthermore, in vivo studies verified that exosomal miR‐92a‐3p notably promoted tumor growth and stemness through targeting AXIN1/β‐catenin axis. Collectively, CAFs secreted exosomal miR‐92a‐3p was capable of promoting growth and stemness in HCC through activation of Wnt/β‐catenin signaling pathway by suppressing AXIN1. Therefore, targeting CAFs‐derived miR‐92a‐3p may be a potential strategy for treating HCC. [ABSTRACT FROM AUTHOR]

Electrochemical reduction of nitrate (NO3RR) holds great promise for environmentally friendly ammonia production. Tandem catalysis is a promising strategy for boosting the NO3RR and inhibiting side effects, but it is still challenged by lacking well‐designed catalysts to drive this catalytic process. Herein, the study develops the CuCo branched nanowires (CuCo NW) catalyst, which efficiently converts NO3 − to NH3 on Co (111) and Cu (111) crystal facets through a tandem catalysis mechanism. The in situ grown CuCo NW on Cu foam demonstrates a remarkable Faraday efficiency of 90.3% at 1.0 A cm−2 and maintains stable operation for 200 h at 100 and 200 mA cm−2 in a flow reactor. Density functional theory calculations suggest that the initial absorption and subsequent deoxygenation of *NO3 on Co (111) leading to the formation of *NO2, followed by its transfer to Cu (111) and further conversion to *NH3, establish an optimal pathway by managing rate‐determining steps on individual surfaces for NO3RR. To showcase the practical application of the catalyst, the study further develops a scaling‐up prototype reactor for continuous ammonia production, realizing the gram‐level yield rate of 1474.09 mg h−1 and Faraday efficiency of 91.26% at practical‐level 20.0 A. [ABSTRACT FROM AUTHOR]

The self‐catalyzed growth of nanostructures on material surfaces is one of the most time‐ and cost‐effective ways to design multifunctional catalysts for a wide range of applications. Herein, the use of this technique to develop a multicomponent composite catalyst with CoSx core encapsulated in an ultrathin porous carbon shell entangled with Co, N‐codoped carbon nanotubes is reported. The as‐prepared catalyst has a superior catalytic activity for oxygen evolution and oxygen reduction reactions, an ultralow potential gap of 0.74 V, and outstanding durability, surpassing most previous reports. Such superiority is ascribed, in part, to the unique 3D electrode architecture of the composite, which is favorable for transporting oxygen species and electrons and creates a synergy between the components with different functionalities. Moreover, the flexible solid Zn–air battery assembled with such an air electrode shows a steady discharge voltage plateau of 1.25 V and a round‐trip efficiency of 70% at 1 mA cm−2. This work presents a simple strategy to design highly efficient bifunctional oxygen electrocatalysts and may pave the way for the practical application of these materials in many energy conversion/storage devices. [ABSTRACT FROM AUTHOR]

A stable stripping/plating process of the zinc anode is extremely critical for the practical application of aqueous zinc metal batteries. However, obstacles, including parasitic reactions and dendrite growth, notoriously deteriorate the stability and reversibility of zinc anode. Herein, Methyl l-α-aspartyl-l-phenylalaninate (Aspartame) is proposed as an effective additive in the ZnSO 4 system to realize high stability and reversibility. Aspartame molecule with rich polar functional groups successfully participates in the solvation sheath of Zn 2+ to suppress water-induced side reactions. The self-driven adsorption of Aspartame on zinc anode improves uniform deposition with a dose of 10 mm. These synergetic functions endow the zinc anode with a significantly long cycling lifespan of 4500 h. The cell coupled with a vanadium-based cathode also exhibited a high-capacity retention of 71.8% after 1000 cycles, outperforming the additive-free counterparts., (© 2024 The Author(s). Small published by Wiley‐VCH GmbH.)

Catalyst-support interaction plays a crucial role in improving the catalytic activity of oxygen evolution reaction (OER). Here we modulate the catalyst-support interaction in polyaniline-supported Ni 3 Fe oxide (Ni 3 Fe oxide/PANI) with a robust hetero-interface, which significantly improves oxygen evolution activities with an overpotential of 270 mV at 10 mA cm -2 and specific activity of 2.08 mA cm ECSA -2 at overpotential of 300 mV, 3.84-fold that of Ni 3 Fe oxide. It is revealed that the catalyst-support interaction between Ni 3 Fe oxide and PANI support enhances the Ni-O covalency via the interfacial Ni-N bond, thus promoting the charge and mass transfer on Ni 3 Fe oxide. Considering the excellent activity and stability, rechargeable Zn-air batteries with optimum Ni 3 Fe oxide/PANI are assembled, delivering a low charge voltage of 1.95 V to cycle for 400 h at 10 mA cm -2 . The regulation of the effect of catalyst-support interaction on catalytic activity provides new possibilities for the future design of highly efficient OER catalysts., (© 2024. The Author(s).)

Redox mediators (RMs) have become a significant point in the now-established Li-O 2 battery system to reduce the charging overpotential in the oxygen evolution process. Nevertheless, a major inherent barrier of the RM is the redox shuttling between the Li metal anode and mobile RM, resulting in the corrosion of Li and depletion of RM. In this study, taking iodide/triiodide as a model RM, we propose an effective strategy by immersing the Li metal anode in I 2 steam to create a 1.5 μm thick surface protective layer. The resultant ionic conductive LiI layer on the Li metal anode can not only suppress Li dendrite growth but also act as a buffer layer between the RM and bare Li. By combining the iodide/triiodide RM with the LiI protective layer, the Li-O 2 battery shows low and steady charge voltage plateaus of ∼3.6 V over 70 cycles. Importantly, the symmetrical cell using the LiI-protected Li electrode exhibited small Li plating/stripping overpotentials (∼20 mV, 480 h), far superior to that of the bare Li electrode (∼70 mV, 300 h). The in situ interfacial observation shows that dendrite growth on the Li metal can be effectively suppressed by optimizing the LiI protective layer.

The cycling performance of Li-O 2 batteries (LOBs), which is an important parameter determining the practical use of this advanced energy technology with ultrahigh energy density, is strongly affected by the nature of the oxygen electrocatalyst. As a good oxygen electrode, it should possess good activity for both the oxygen evolution reaction and the oxygen reduction reaction and superior stability under operating conditions. During the past, oxygen electrodes for LOBs were generally fabricated by loading noble metal nanoparticles on the surface of a porous carbon support. However, the nanoparticles could easily lose contact with the carbon support during the reversible liquid-gas-solid reactions that involve lithium ions, oxygen gas, and Li 2 O 2 . Herein, we reported a novel Ru-metal-organic framework (MOF)-derived carbon composite, characterized by stereoscopic Ru nanoparticle distribution within the carbon matrix, as an alternative oxygen catalyst of LOBs, enabling superior operational stability and favorable activity. More specifically, the battery demonstrated stable charge-discharge cycling for up to 800 times (∼107 days) at a current density of 500 mA g -1 with low discharge/charge overpotentials (∼0.2/0.7 V vs Li). A mechanism of regenerative surface was further proposed to explain the excellent cycling stability of the LOBs through the use of the Ru-MOF-C catalyst. These encouraging results imply an accessible solution to address issues related to the oxygen catalyst for the realization of practical LOBs.

Gel-polymer electrolytes are considered as a promising candidate for replacing the liquid electrolytes to address the safety concerns in Li-O 2 /air batteries. In this work, by taking advantage of the hydrogen bond between thermoplastic polyurethane and aerogel SiO 2 in gel polymer, a highly crosslinked quasi-solid electrolyte (FST-GPE) with multifeatures of high ionic conductivity, high mechanical flexibility, favorable flame resistance, and excellent Li dendrite impermeability is developed. The resulting gel-polymer Li-O 2 /air batteries possess high reaction kinetics and stabilities due to the unique electrode-electrolyte interface and fast O 2 diffusion in cathode, which can achieve up to 250 discharge-charge cycles (over 1000 h) in oxygen gas. Under ambient air atmosphere, excellent performances are observed for coin-type cells over 20 days and for prototype cells working under extreme bending conditions. Moreover, the FST-GPE electrolyte also exhibits durability to protect against fire, dendritic Li, and H 2 O attack, demonstrating great potential for the design of practical Li-O 2 /air batteries., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)