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Structural degradation of oxide electrodes during the electrocatalytic oxygen evolution reaction (OER) is a major challenge in water electrolysis. Although the OER is known to induce changes in the surface layer, little is known about its effect on the bulk of the electrocatalyst and its overall phase stability. Here, we show that under OER conditions, a highly active SrCoO 3- x electrocatalyst develops bulk lattice instability, which results in the formation of molecular O 2 dimers inside the bulk and nanoscale amorphization induced via chemo-mechanical coupling. Using high-resolution resonant inelastic X-ray scattering and first-principles calculations, we unveil the potential-dependent evolution of lattice oxygen inside the perovskite and demonstrate that O 2 dimers are stable in a densely packed crystal lattice, thus challenging the assumption that O 2 dimers require sufficient interatomic spacing. We also show that the energy cost of local atomic rearrangements in SrCoO 3- x becomes very low under the OER conditions, leading to an unusual amorphization under intercalation-induced stress. As a result, we propose that the amorphization energy can be calculated from the first principles and can be used to assess the stability of electrocatalysts. Our study demonstrates that extreme oxidation of electrocatalysts under OER can intrinsically destabilize the lattice and result in bulk anion redox and disorder, suggesting why some oxide materials are unstable and develop a thick amorphous layer under water electrolysis conditions.

This study reveals a charging mechanism at oxide-water interfaces, solving the puzzle that challenges the traditional electrical double layer (EDL) model. We found that the experimentally measured zeta potential is caused by physically adsorbed OH - , instead of acidic dissociation of surface OHs and the first-layer water. This mechanism should apply for a wide range of material interfaces and could find applications in future.

Metal oxides are promising (photo)electrocatalysts for sustainable energy technologies due to their good activity and abundant resources. Their applications such as photocatalytic water splitting predominantly involve aqueous interfaces under electrochemical conditions, but in situ probing oxide-water interfaces is proven to be extremely challenging. Here, we present an electrochemical scanning tunneling microscopy (EC-STM) study on the rutile TiO 2 (110)-water interface, and by tuning surface redox chemistry with careful potential control we are able to obtain high quality images of interfacial structures with atomic details. It is interesting to find that the interfacial water exhibits an unexpected double-row pattern that has never been observed. This finding is confirmed by performing a large scale simulation of a stepped interface model enabled by machine learning accelerated molecular dynamics (MLMD) with ab initio accuracy. Furthermore, we show that this pattern is induced by the steps present on the surface, which can propagate across the terraces through interfacial hydrogen bonds. Our work demonstrates that by combining EC-STM and MLMD we can obtain new atomic details of interfacial structures that are valuable to understand the activity of oxides under realistic conditions., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The rodent running-wheel recording apparatus is a reliable approach for studying circadian rhythm. This study demonstrated how to construct a simple and intelligent running-wheel recording system. The running wheel was attached to the cage's base, whereas the Hall sensor was attached to the cage's cover. Then, the RJ25 adaptor relayed the running signal to the main control board. Finally, the main control board was connected to the USB port of the computer with the USB connection. Data were collected using the online-accessible, self-created software Magturning. Through Magturning, generated data were saved and exported in real time. Afterward, the device was validated by collecting data on the locomotor activities of mice under different light conditions. In conclusion, this new device can record circadian activity of rodents. Our device is appropriate for interdisciplinary investigations related to biological clock research., (© 2024 The Authors. Animal Models and Experimental Medicine published by John Wiley & Sons Australia, Ltd on behalf of The Chinese Association for Laboratory Animal Sciences.)

Semiconductor alloy materials are highly versatile due to their adjustable properties; however, exploring their structural space is a challenging task that affects the control of their properties. Traditional methods rely on ad hoc design based on the understanding of known chemistry and crystallography, which have limitations in computational efficiency and search space. In this work, we present ChecMatE (Chemical Material Explorer), a software package that automatically generates machine learning potentials (MLPs) and uses global search algorithms to screen semiconductor alloy materials. Taking advantage of MLPs, ChecMatE enables a more efficient and cost-effective exploration of the structural space of materials and predicts their energy and relative stability with ab initio accuracy. We demonstrate the efficacy of ChecMatE through a case study of the InxGa1-xN system, where it accelerates structural exploration at reduced costs. Our automatic framework offers a promising solution to the challenging task of exploring the structural space of semiconductor alloy materials., (© 2023 Author(s). Published under an exclusive license by AIP Publishing.)

Aqueous rutile TiO 2 (110) is the most widely studied water-oxide interface, and yet questions about water dissociation are still controversial. Theoretical studies have systematically investigated the influence of the slab thickness on water dissociation energy (E diss ) at 1 monolayer coverage using static density functional theory calculation and found that E diss exhibits odd-even oscillation with respect to the TiO 2 slab thickness. However, less studies have accounted for the full solvation of an aqueous phase using ab initio molecular dynamics due to high computational costs in which only three, four, and five trilayer models of rutile(110)-water interfaces have been simulated. Here, we report Machine Learning accelerated Molecular Dynamics (MLMD) simulations of defect-free rutile(110)-water interfaces, which allows for a systematic study of the slab thickness ranging from 3 to 17 trilayers with much lower costs while keeping ab initio accuracy. Our MLMD simulations show that the dissociation degree of surface water (α) oscillates with the slab thickness and converges to ∼2% as the TiO 2 slab becomes thicker. Converting α into dissociation free energy (ΔA diss ) and comparing with dissociation total energy E diss calculated with a single monolayer of water, we find that the full solvation of the interfaces suppresses surface water from dissociating. It is interesting to note that the machine learning potential trained from the dataset containing exclusively the five trilayer TiO 2 model exhibits excellent transferability to other slab thicknesses and further captures the oscillating behavior of surface water dissociation. Detailed analyses indicate that the central plane in odd trilayer slabs modulates the interaction between double trilayers and, thus, the bonding strength between terminal Ti and water, which affects pKa of surface water and water dissociation degree.

Electrode potential is the key factor for controlling electrocatalytic reactions at electrochemical interfaces, and moreover, it is also known that the pH and solutes (e.g., cations) of the solution have prominent effects on electrocatalysis. Understanding these effects requires microscopic information on the electrochemical interfaces, in which theoretical simulations can play an important role. This Perspective summarizes the recent progress in method development for modeling electrochemical interfaces, including different methods for describing the electrolytes at the interfaces and different schemes for charging up the electrode surfaces. In the final section, we provide an outlook for future development in modeling methods and their applications to electrocatalysis.

Online Social networks exhibit heterogeneous nature with nodes playing far different roles in structure and function. To identify influencers is thus very significant, allowing us to control the outbreak of public negative opinion, to conduct advertisements for e-commercial products, to predict popular scientific publications, and so on. The identification of influencers attracts increasing attentions from both computer science and communication science, with multiple dimensional metrics ranging from structure-based to information-based and action-based. However, most work simply rely on one dimensional metrics. Therefore, in this paper, we analyze three dimensional characteristics (structure-based, information-based, and action-based factors) to develop the multidimensional social influence (MSI) measurement approach. With topic distillation and conditional expectation, the MSI approach can not only measure users topic-level influence, but also measure users global-level influence. Based on data collected from SinaWeibo.com, the experimental results show that the proposed framework outperforms two traditional methods (LeaderRank and FBI) both on the topic-level and the global-level. The proposed framework can be effectively applied to promote word-of-mouth marketing, and to steer public opinion in certain directions, even to support decisions during a negotiation process., Competing Interests: The authors declare no conflict of interest., (© 2021 The Author(s).)

In order to explore the mechanism of gefitinib-acquired resistance in lung cancer, a new biomarker has been developed for early clinical diagnosis and intervention; human NSCLC (Non-Small Cell Lung Cancer) cell lines H292 (denoted as H292S) and PC9 (denoted as PC9S) were used to establish gefitinib-resistant NSCLC cell lines H292 and PC9 models. CCK-8 (Cell Counting Kit-8) method was used to test the drug resistance of the cells. circRNAs (circular RNAs) that were differentially expressed before and after resistance were screened by RNA sequencing technology. The effects of circSETD3 overexpression and interference on the sensitivity of gefitinib was observed to analyze the nuclear localization of circSETD3 and verify the interaction between circSETD3-miR-520h-ABCG2. The results showed that the most significant change in differential expression of human NSCLC cell lines before and after drug resistance was hsa_circ_0000567, that is, circSETD3, which is mainly present in the cytoplasm. In H292S and PC9S, compared with the negative control group, the cell proliferation ability of the overexpression group was significantly increased, and the apoptosis ability was significantly decreased. In H292R and PC9R, compared with the negative control group, the proliferation ability of the interference group was significantly decreased, and the apoptosis ability was significantly increased. Overexpression of circSETD3 to H292S and PC9S, the expression of ABCG2 increased significantly. Also, the expression of ABCG2 decreased significantly after transfection with miR-520h mimics. H292R and PC9R interfered with circSETD3, the expression of ABCG2 decreased significantly. Moreover, the expression of ABCG2 increased significantly after transfection with miR-520h inhibitor. In conclusion, circSETD3 can be used as a novel biomarker for lung cancer. It relieves miR-520h degradation of the transporter ABCG2 by down-regulating the miR-520h expression, causing gefitinib to be pumped out of the cell., (Copyright 2020 Biolife Sas. www.biolifesas.org.)

Gold nanoclusters (AuNCs) have attracted much attention as signal transducers in photoluminescence chemical/biological sensors. Herein, we employ bovine serum albumin/3-mercaptopropionic acid co-modified AuNCs as a fluorescence probe, Fe 3+ as a quencher, and pyrophosphate as an alkaline phosphatase (ALP) substrate and Fe 3+ chelator to design a novel biosensor for ALP detection, achieving a detection linear range of 0.8-16 U/L and a detection limit of 0.78 U/L. The developed method is successfully applied to the detection of ALP in human osteosarcoma cells and is shown to be suited for ALP inhibitor screening., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2019. Published by Elsevier B.V.)

Background: Patients with previously treated non-small-cell lung cancer (NSCLC) have limited treatment options. A novel treatment based on programmed death 1 (PD-1)/programed death ligand 1 (PD-L1) inhibitors has emerged as promising therapeutic options for advanced NSCLC. We assessed oncological outcomes of PD-L1 antibody versus docetaxel in previously treated NSCLC., Objectives: The purpose of this meta-analysis was to analyse the oncological outcomes of anti-PD1 to chemotherapy in the treatment of non-small-cell lung cancer., Results: Overall survival (OR=0.68,95%CI=0.61-0.75, P<0.00001) and progression-free survival (OR=0.84,95%CI=0.77-0.92, P=0.0002) were longer with anti-PD1 than with docetaxel in NSCLC. Anti-PD1 was associated with even greater objective response rate than docetaxel (OR=1.61,95%CI=1.16-2.24, P=0.004). Treatment-related adverse events of grade 3-5 did favor anti-PD1 over docetaxel (OR=0.21,95%CI=0.10-0.42, P<0.00001)., Conclusions: Among patients with advanced NSCLC, we found that there was a superior survival benefit and with a favorable safety profile with anti-PD1 than with docetaxel. More large-scale randomized controlled trials are needed to identify relevant biomarkers that have an effect on predicting the population that would most likely benefit from PD-1/PD-L1 for pretreated advanced NSCLC patients., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

The North American pink heelsplitter (Potamilus alatus) differs from most freshwater mussels in China by the ability to secrete an ephemeral byssus during its juvenile stage. In the present study, light microscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM) were used to investigate this ephemeral byssal structure, and amino acid composition was analyzed and compared with that of other species. The results revealed that the byssus consists of a long byssal thread and a few adhesive plaques which are randomly set up along the thread and assembled by petioles. There is a thin but distinctive cuticle with a continuous homogeneous matrix surrounding the byssal thread. Structural variation occurred when the byssal thread was differentially stretched. Four-stranded helical primary fasciculi, which form a stable rope-like structure, become evident after removal of the cuticle. The primary fasciculi consist of bundles of hundreds of parallel secondary fasciculi, each measuring about 5 μm in diameter. All evidence indicates that the byssus of the pink heelsplitter has a significantly different macrostructure and microstructure than the permanent byssus of the marine mussel Mytilus. Byssogenesis ceases when juveniles exceed 30 mm in length, although it varies greatly even among juveniles of similar size. Byssus formation is influenced by substrate type. The unique characteristics of the byssus have important advantages for survival, transition, and aggregation during the early life history. This study not only provides first insight into the structure of the ephemeral byssus and its relationship to freshwater mussel development and growth, but also suggests possibilities for the synthesis of novel biopolymer materials particularly useful in freshwater ecosystems., (© 2015 Wiley Periodicals, Inc.)

Costunolide, the main bioactive compound of the medicinal plant, Radix Aucklandiae, is a sesquiterpene lactone (SL) and has a broad range of biological activities. It is also a precursor of many biologically-active SLs and is a branching point in the biosynthesis of SLs. Here we have reconstituted the costunolide biosynthetic pathway in Escherichia coli by co-expression of three genes (GAS, GAO, LsCOS) involved in costunolide biosynthesis and eight genes involved in converting acetyl-CoA into farnesyl diphosphate from mevalonate pathway. Costunolide production was then detected. By screening and optimization of cultured medium and inducing temperature, costunolide yield was up to 100 mg l(-1) in E. coli.