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An automated framework for exploring and learning potential-energy surfaces
Abstract Machine learning has become ubiquitous in materials modelling and now routinely enables large-scale atomistic simulations with quantum-mechanical accuracy. However, developing machine-learned interatomic potentials requires high-quality training data, and the manual generation and curation of such data can be a major bottleneck. Here, we introduce an automated framework for the exploration and fitting of potential-energy surfaces, implemented in an openly available software package that we call (‘automatic potential-landscape explorer’). We discuss design choices, particularly the interoperability with existing software architectures, and the ability for the end user to easily use the computational workflows provided. We show wide-ranging capability demonstrations: for the titanium–oxygen system, SiO2, crystalline and liquid water, as well as phase-change memory materials. More generally, our study illustrates how automation can speed up atomistic machine learning in computational materials science.
HBV reactivation and prognosis after systemic therapy in HCC with undetectable HBV DNA: a multicenter retrospective study
Gene duplication and clustering underlie the conservation and diversification of benzylisoquinoline alkaloid biosynthesis in plants
Unveiling diurnal metamorphosis in the atmospheric boundary layer during an annular solar eclipse through large eddy simulations
Noncanonical roles of chemokine regions in CCR9 activation revealed by structural modeling and mutational mapping
Abstract The G protein-coupled chemokine receptor CCR9 plays a major role in inflammatory bowel disease and is implicated in cancer. Despite its therapeutic relevance, the mechanism by which CCR9 is activated by its endogenous chemokine CCL25 remains poorly understood. Here, we combine structural modeling with multimodal pharmacological analysis of CCR9 mutants to map the CCR9–CCL25 interface and delineate key determinants of binding, G protein versus arrestin signaling, and constitutive activity. We show that unlike other chemokines which drive receptor activation through their N-termini, CCL25 activates CCR9 via a distinct region, its 30s loop. Supporting this non-canonical mechanism, CCR9 signaling tolerates alanine mutations in the CCL25 N-terminus but is strongly affected by 30s loop modifications. Engineered N-terminally modified CCL25 analogs remain full agonists, consistent with signaling determinants lying outside the N-terminus. This non-canonical activation signature provides insights for CCR9 drug discovery and may inform structure-based design for other chemokine receptors.
Copper‐Tailored Molybdenum–Nickel Catalyst Boosts Hydrogen Oxidation and Suppresses Parasitic Oxygen Reduction for Durable Fuel Cells
Abstract Numerous existing strategies struggle to mitigate reverse‐current decay (RCD) during startup and shutdown in polymer electrolyte fuel cells to avoid cathode corrosion, but the added system complexity and cost are drawbacks. Here, we report that modification of a molybdenum–nickel alloy through the doping of copper enables a non‐noble electrocatalyst (MoNi 3.6 Cu 0.4 ) that efficiently catalyzes hydrogen oxidation reaction (HOR) while catalytically inactive toward oxygen reduction reaction (ORR) in alkaline media, making it ideal for fuel‐cell anode because the instantaneous interfacial potential jump originated from the parasitic ORR during device startup/shutdown can be surmounted. The catalyst, when assembled in the anode of an anion exchange membrane fuel cell, manifests substantially improved corrosion‐resistant ability compared with that of state‐of‐the‐art carbon‐supported platinum (Pt/C) catalyst. The basis for the achieved performances reveals to be the copper dopants that increase the hydrogen bonding of interfacial water for enhanced HOR, yet weaken molecular oxygen adsorption while stabilizing hydroxyl adsorption for ORR suppression.
Molecular epidemiology of foot and mouth disease virus in Iran during 2019 and 2023
Operando neutron imaging-guided gradient design of Li-ion solid conductor for high-mass-loading cathodes
The roots of belonging: childhood predictors of belonging in 22 countries
Structural dynamics of melting and glass formation in a two-dimensional hybrid perovskite
Abstract Hybrid organic-inorganic perovskites (HOIPs) have garnered significant attention for their crystalline properties, yet recent findings reveal that they can also form liquid and glassy phases, offering an alternative platform for understanding non-crystalline materials. In this study, we present a detailed investigation into the structural dynamics of the melting and glass formation process of a two-dimensional (2D) HOIP, (S−(−)−1-(1−naphthyl)ethylammonium)2PbBr4. Compared to its crystalline counterpart, the glass exhibits superior mechanical properties, including higher Young’s modulus and hardness. Our structural studies reveal that the liquid and glass formed from the 2D HOIP exhibit network-forming behaviour, featuring limited short-range order within individual octahedra, partial retention of metal-halide-metal connectivity between neighbouring octahedra, and residual structural correlations mediated by organic cations. We then combine in situ variable-temperature X-ray total scattering experiments, terahertz far-infrared absorption spectroscopy and solid-state nuclear magnetic resonance techniques to study the melting mechanism and the nature of the HOIP liquid obtained. Our results deepen the understanding of the structural evolution and property relationships in HOIP glasses, providing a foundation for their potential applications in advanced phase-change material technologies.
Building a Bridge Between Ambient MS and LC‐MS by Non‐Exhaustive Microdesorption
Abstract Ambient mass spectrometry (AMS) offers rapid screening but faces challenges in analyzing complex samples due to high matrix effects. The absence of a separation step can also lead to false positives due to the isomers or isobars. In this study, a sequential analysis strategy which combines ambient MS and LC‐MS based on the non‐exhaustive microdesorption in solid‐phase microextraction (SPME) was developed for the first time. By combining coated blade spray (CBS)‐MS with LC‐MS, in the first step, a few microliters of solvent were used for non‐exhaustive desorption with high enrichment factor for rapid screening by CBS‐MS. For the suspicious samples, the remaining analytes on the SPME coating undergo exhaustive desorption, then followed by LC‐MS confirmation. The matrix‐compatible coating used in the SPME device significantly reduces matrix effects while enhancing sensitivity through analyte enrichment. This method is environmentally friendly, utilizing only a few microliters of organic solvents for screening. The approach was rigorously validated, both theoretically and experimentally, and successfully applied to anti‐doping testing, enabling detection of 53 prohibited substances in urine samples by integrating CBS‐MS with LC‐MS.
Photoelectric/Photothermal Synergy Activation in Floating Aerogel Cathode Breaks Neutral Triphase Reaction Barriers for High‐Efficiency Full‐Spectrum‐Responsive Seawater Batteries
Abstract Harnessing natural resources (solar, seawater) to explore next‐generation sustainable energy storage is an intriguing yet challenging task. Here, we establish a unique floating photoelectric/photothermal dual‐activated catalytic platform based on engineered Janus aerogel that overcomes inherent mass transport/kinetics constraints in neutral triphase oxygen reaction systems to enable a full‐spectrum‐responsive seawater battery with ultrahigh energy efficiency. Our approach employs in situ region‐selective assembly of the rationally designed fluorinated donor–acceptor polymers on carbon‐nanotube aerogel (FMTAPPC), creating a new floatable FMTAPPC photoelectrode with asymmetric wettability, superior photoelectric/photothermal dual‐response, and bifunctional oxygen evolution/reduction (OER/ORR) catalysis. This all‐in‐one integration enables floating FMTAPPC to maximize sunlight utilization for interface micro‐environment regulation and adsorbate binding optimization via photoelectric/photothermal dual‐activation while satisfying paradoxical wetting requirements of OER/ORR, which tunes reaction kinetics and intermediate energetics to remarkably promote both OER/ORR in neutral media. Under sunlight, floating FMTAPPC delivers large current densities for both OER/ORR–3–4 fold‐enhancement over dark conditions. This enables the seawater‐based Zn–air battery to simultaneously improve charge/discharge performance at high rates and deliver ultrahigh round‐trip efficiency of 128.2%—surpassing most photo‐assisted batteries. Mechanistic studies unveil that photoelectric/photothermal effects synergistically boost OER/ORR kinetics, while the photoelectric effect dominates intermediate energetics optimization, substantially lowering reaction energy barriers.
A study of the correlation between urinary perchlorate, nitrate, thiocyanate, and serum liver function indices
AI-powered spatiotemporal imputation and prediction of chlorophyll-a concentration in coastal ecosystems
Engineered C–N Lyases for Stereoselective Synthesis of Tertiary Amines
Abstract Optically pure N ‐functionalized α‐amino acids are valuable chiral building blocks for pharmaceuticals, nutraceuticals, and agrochemicals. Ethylenediamine‐ N,N ‐disuccinic acid lyase from Chelativorans sp. BNC1 catalyzes the addition of a wide range of aliphatic and aromatic primary amines to fumarate, producing the corresponding enantioenriched N ‐substituted L‐ aspartic acids. In this work, the enzyme was subjected to iterative cycles of site‐saturation mutagenesis and screened for increased activity for the addition of 2‐((methylamino)methyl)aniline to fumarate. The final variant displayed an activity of three orders of magnitude higher compared to the wild‐type enzyme. Unexpectedly, the enzyme catalyzed the hydroamination of fumarate with the aliphatic secondary amine of the starting substrate, rather than with the aromatic primary amine, leading to the formation of a tertiary amine. Exploring the substrate scope showed that the enzyme accepts various substituted N ‐methyl‐1‐phenylmethanamines for the hydroamination of fumarate, yielding N,N ‐disubstituted L ‐aspartic acids in high optical purity (up to >99% ee). Furthermore, we showed that the enzyme accepts several ortho ‐substituted anilines that were previously not accepted by the wild‐type enzyme, yielding the corresponding N ‐arylated L ‐aspartic acids in high enantiomeric excess (>99% ee). This serendipitous finding enables a new strategy for the biocatalytic synthesis of tertiary amines, unlocked within the C‐N lyase toolbox.
Prevalence of paediatric diarrhoea in Arba minch government health institutions, Southern Ethiopia and associated factors
Targeting intestinal inflammation using locked nucleic acids delivered via lipid nanoparticles
Upconversion Lanthanide‐Based 2D Metal‐Organic Frameworks for Multimode Information Encryption
Abstract Luminescent 2D metal‐organic frameworks (MOFs) are a class of metal‐organic framework materials expanded in a 2D plane, which have a wide range of applications in fields of optoelectronic devices, sensors, and information storage due to their unique layered structure and excellent optical properties. Currently, research on luminescent 2D MOFs mainly focuses on down‐shifting luminescence, while the exploration of upconversion luminescence remains in its early stages. Herein, a novel 2D Yb‐PMA MOFs were synthesized, and red upconversion luminescence at 660 nm under 980 nm excitation was successfully achieved by introducing Ho 3+ as the luminescence center and using Yb 3+ as the sensitizer. In addition, multimode emitting MOFs with both upconversion and down‐shifting luminescence were further constructed by codoping Tb 3+ or Eu 3+ . Inspired by the layered structure of 2D materials, multilayer stacked 2D MOFs composites were prepared by ultrasonic exfoliation method and upconversion luminescence was realized for the first time by interfacial energy transfer between different components. This strategy not only expands the optical modulation of luminescent 2D MOFs, but also provides new ideas for the construction of multifunctional luminescent materials. The upconversion/down‐shifting luminescent lanthanide‐based 2D MOFs designed in this work show good potential for application in the field of information encryption.
Artificial intelligence-assisted optimization of Eichhornia crassipes extracts and evaluation of their biological activities
Abstract In this research, the extraction conditions for Eichhornia crassipes (Mart.) Solms were optimized using Response Surface Methodology (RSM) and Artificial Neural Network–Genetic Algorithm (ANN–GA) techniques to enhance the biological efficacy of the extracts. The optimization focused on three key variables: extraction temperature, duration, and the ethanol-to-water solvent ratio. Through the ANN–GA model, the optimal parameters were identified as 56.85 °C for temperature, 7.62 h for extraction time, and 23.93% for the ethanol/water proportion. The obtained extracts showed statistically significantly higher values compared to RSM in terms of antioxidant capacity (FRAP: 152.89 mg TE/g; DPPH: 121.48 mg TE/g), total phenolic content (TPC: 209.47 mg GAE/g) and flavonoid content (TFC: 263.86 mg QE/g). In addition, ANN–GA extract exhibited high anticholinesterase activity with lower IC₅₀ values against acetylcholinesterase (AChE: 61.69 µg/mL) and butyrylcholinesterase (BChE: 81.40 µg/mL) enzymes. In in vitro tests on A549 cell line, its antiproliferative effect increased significantly in a dose-dependent manner and significant decreases in cell viability were observed especially at high concentrations. LC-MS/MS analyses revealed that pharmacologically important phenolic compounds such as quercetin (10295.26 mg/kg), kaempferol (8656.31 mg/kg) and naringenin (5364.56 mg/kg) were present in high concentrations in the optimized extracts. In conclusion, ANN–GA based extraction approach stands out as an effective method for obtaining phenolic compound rich and biologically effective extracts of E. crassipes. These findings indicate that this aquatic plant should be evaluated for its pharmaceutical, neuroprotective and anticancer potential.