Machine Learning-Accelerated First-Principles Molecular Dynamics Explains Anomalous Lattice Thermal Expansion in BaZrYO.

Fuel cells are a vital clean energy technology that converts chemical energy directly into electricity with high efficiency, making them a cornerstone of a sustainable energy future. Herein, we investigate the thermal and chemical lattice expansion behavior of hydrated BaZrYO using machine learning-accelerated molecular dynamics simulations. Our results reproduce the experimentally observed nonmonotonic and anomalous temperature dependence of lattice expansion, which we attribute to the competing effects of thermal expansion and dehydration, two mechanisms that influence the lattice expansion in opposite directions.

Prevalence and the associated factors of burnout among the critical healthcare professionals during the post-pandemic era: a multi-institutional survey in Taiwan with a systematic review of the Asian literatures.

Background & Aims: Burnout is a global concern, and critical healthcare professionals have been identified as a high-risk population of burnout. Early identification is crucial, but the prevalence of burnout and its risk factors demonstrate significant geographical variations. This study aims to investigate the prevalence of burnout among critical healthcare professionals and explore potential risk factors during the post-pandemic era in Taiwan.

Using computed tomography to evaluate anatomic landmarks in Taiwanese trauma patients for insertion of resuscitative endovascular balloon occlusion of the aorta: a retrospective cohort study.

Background: Hemorrhage, particularly from noncompressible torso hemorrhage (NCTH) in the abdominopelvic region, is a leading cause of preventable trauma deaths. Resuscitative endovascular balloon occlusion of the aorta (REBOA), designed for aortic occlusion, has emerged as a tool for temporary hemorrhage control in recent years. However, attaining optimal REBOA placement in diverse demographic groups, such as Asian populations, may pose challenges owing to unique anatomical and physiological differences.

Serum vascular endothelial growth factor affects tissue fluid accumulation and is associated with deteriorating tissue perfusion and oxygenation in severe sepsis: a prospective observational study.

Background: Positive fluid balance and tissue fluid accumulation are associated with adverse outcomes in sepsis. Vascular endothelial growth factor (VEGF) increases in sepsis, promotes vascular permeability, and may affect tissue fluid accumulation and oxygenation. We used near-infrared spectroscopy (NIRS) to estimate tissue hemoglobin (Hb) oxygenation and water (HO) levels to investigate their relationship with serum VEGF levels.

Recurrent right hepatic artery pseudoaneurysm after robotic-assisted cholecystectomy in a patient with Mirizzi syndrome: a case report.

Background: Iatrogenic hepatic artery pseudoaneurysm is a rare complication following laparoscopic cholecystectomy. Trans-arterial embolization (TAE) is an effective way to control bleeding after a ruptured aneurysm. But uncommonly, rebleeding may occur which will require a second embolization or even laparotomy.

Inferior Vena Cava Volume Is an Independent Predictor of Massive Transfusion in Patients With Trauma.

Objectives: Early adequate resuscitation of patients with trauma is crucial in preventing shock and early mortality. Thus, we aimed to determine the performance of the inferior vena cava (IVC) volume and other risk factors and scores in predicting massive transfusion and mortality.

Methods: We included all patients with trauma who underwent computed tomography (CT) scan of the torso, which included the abdominal area, in our emergency department (ED) from January 2014 to January 2017.

Diagnosis of a maxillary sinus fungus ball without intralesional hyperdensity on computed tomography.

Objectives/hypothesis: Maxillary sinus fungus ball (MSFB) is the most common type of noninvasive fungal rhinosinusitis. Surgical removal of the ball achieves good outcomes. Making a rapid and accurate diagnosis is important to avoid unnecessary medical therapy.

Erratum: Activate lattice oxygen redox reactions in metal oxides to catalyse oxygen evolution.

This corrects the article DOI: 10.1038/nchem.2695.

Modeling of the oxygen reduction reaction for dense LSM thin films.

In the present study, the oxygen reduction reaction mechanism is investigated using numerical methods on a dense thin (LaSr)MnO film deposited on a YSZ substrate. This 1-D continuum model consists of defect chemistry and elementary oxygen reduction reaction steps coupled via reaction rates. The defect chemistry model contains eight species including cation vacancies on the A- and B-sites.

Quantitative interpretation of impedance spectroscopy data on porous LSM electrodes using X-ray computed tomography and Bayesian model-based analysis.

It is broadly understood that strontium-doped lanthanum manganate (LSM) cathodes for solid oxide fuel cells (SOFCs) have two pathways for the reduction of oxygen: a surface-mediated pathway culminating in oxygen incorporation into the electrolyte at the triple-phase boundary (TPB), and a bulk-mediated pathway involving oxygen transfer across the electrode-electrolyte interface. Patterned electrode and thin film experiments have shown that both pathways are active in LSM. Porous electrode geometries more commonly found in SOFCs have not been amenable for precise measurement of active electrode width because of the difficulty in precisely measuring the electrode geometry.

Addendum: Activating lattice oxygen redox reactions in metal oxides to catalyse oxygen evolution.

This corrects the article DOI: 10.1038/nchem.2695.

Activating lattice oxygen redox reactions in metal oxides to catalyse oxygen evolution.

Understanding how materials that catalyse the oxygen evolution reaction (OER) function is essential for the development of efficient energy-storage technologies. The traditional understanding of the OER mechanism on metal oxides involves four concerted proton-electron transfer steps on metal-ion centres at their surface and product oxygen molecules derived from water. Here, using in situ O isotope labelling mass spectrometry, we provide direct experimental evidence that the O generated during the OER on some highly active oxides can come from lattice oxygen.

Correlation of nanoscale behaviour of forces and macroscale surface wettability.

In this manuscript, we demonstrate a method based on atomic force microscopy which enables local probing of surface wettability. The maximum pull-off force, obtained from force spectroscopy shows a remarkable correlation with the macroscopically observed water contact angle, measured over a wide variety of surfaces starting from hydrophilic, all the way through to hydrophobic ones. This relationship, consequently, facilitates the establishment of a universal behaviour.

Oxygen Point Defect Chemistry in Ruddlesden-Popper Oxides (La1-xSrx)2MO4±δ (M = Co, Ni, Cu).

Stability of oxygen point defects in Ruddlesden-Popper oxides (La1-xSrx)2MO4±δ (M = Co, Ni, Cu) is studied with density functional theory calculations to determine their stable sites, charge states, and energetics as functions of Sr content (x), transition metal (M), and defect concentration (δ). We demonstrate that the dominant O point defects can change between oxide interstitials, peroxide interstitials, and vacancies. In general, increasing x and atomic number of M stabilizes peroxide over oxide interstitials as well as vacancies over both peroxide and oxide interstitials; increasing δ destabilizes both oxide interstitials and vacancies but barely affects peroxide interstitials.

Catalytic Activity and Stability of Oxides: The Role of Near-Surface Atomic Structures and Compositions.

Electrocatalysts play an important role in catalyzing the kinetics for oxygen reduction and oxygen evolution reactions for many air-based energy storage and conversion devices, such as metal-air batteries and fuel cells. Although noble metals have been extensively used as electrocatalysts, their limited natural abundance and high costs have motivated the search for more cost-effective catalysts. Oxides are suitable candidates since they are relatively inexpensive and have shown reasonably high activity for various electrochemical reactions.

Correction: Ab initio and empirical defect modeling of LaMnO3±δ for solid oxide fuel cell cathodes.

Correction for 'Ab initio and empirical defect modeling of LaMnO3±δ for solid oxide fuel cell cathodes' by Yueh-Lin Lee et al., Phys. Chem.

Kinetics of Oxygen Surface Exchange on Epitaxial Ruddlesden-Popper Phases and Correlations to First-Principles Descriptors.

Through alignment of theoretical modeling with experimental measurements of oxygen surface exchange kinetics on (001)-oriented La2-xSrxMO4+δ (M = Co, Ni, Cu) thin films, we demonstrate here the capability of the theoretical bulk O 2p-band centers to correlate with oxygen surface-exchange kinetics of the Ruddlesden-Popper oxide (RP214) (001)-oriented thin films. In addition, we demonstrate that the bulk O 2p-band centers can also correlate with the experimental activation energies for bulk oxygen transport and oxygen surface exchange of both the RP214 and the perovskite polycrystalline materials reported in the literature, indicating the effectiveness of the bulk O 2p-band centers in describing the associated energetics and kinetics. We propose that the opposite slopes of the bulk O 2p-band center correlations between the RP214 and the perovskite materials are due to the intrinsic mechanistic differences of their oxygen surface exchange kinetics and bulk anionic transport.

Joint Experimental and Computational O and H Solid State NMR Study of BaInO(OH) Structure and Dynamics.

A structural characterization of the hydrated form of the brownmillerite-type phase BaInO, BaInO(OH), is reported using experimental multinuclear NMR spectroscopy and density functional theory (DFT) energy and GIPAW NMR calculations. When the oxygen ions from HO fill the inherent O vacancies of the brownmillerite structure, one of the water protons remains in the same layer (O3) while the second proton is located in the neighboring layer (O2) in sites with partial occupancies, as previously demonstrated by Jayaraman et al. (Solid State Ionics2004, 170, 25-32) using X-ray and neutron studies.

Activity and stability trends of perovskite oxides for oxygen evolution catalysis at neutral pH.

Perovskite oxides (ABO3) have been studied extensively to promote the kinetics of the oxygen evolution reaction (OER) in alkaline electrolytes. However, developing highly active catalysts for OER at near-neutral pH is desirable for many photoelectrochemical/electrochemical devices. In this paper, we systematically studied the activity and stability of well-known perovskite oxides for OER at pH 7.

Ab initio GGA+U study of oxygen evolution and oxygen reduction electrocatalysis on the (001) surfaces of lanthanum transition metal perovskites LaBO₃ (B = Cr, Mn, Fe, Co and Ni).

In this work, we performed density functional theory (DFT) calculations with inclusion of Hubbard U corrections for the transition metal d-electrons, to investigate stability and electrocatalytic activities of the oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) for the ABO3 (A = La; B = Cr, Mn, Fe, Co, and Ni) (001) surfaces. We showed surface binding energies of relevant ORR/OER species are coupled strongly to surface polarity and local oxidation states, giving large (∼1 eV scale per adsorbate) differences in binding between (001) AO and BO2 surfaces, where the more oxidized BO2 bare surfaces in general exhibit weak coverage dependence, while the more reduced AO bare surfaces of the LaCrO3, LaMnO3, and LaFeO3 perovskites with lower d-electron filling show strong/moderate coverage dependences. We then predicted that surface coverage can play a key role in determining surface stability, and when coverage effects are included the AO and BO2(001) surfaces have either similar stability or the AO surface is more stable, as found for 1 monolayer HO* covered AO surfaces of LaCrO3 and LaFeO3 under ORR conditions and 1 monolayer O* covered LaNiO3 AO surface under OER conditions.

Anomalous Interface and Surface Strontium Segregation in (La1-ySry)2CoO4±δ/La1-xSrxCoO3-δ Heterostructured Thin Films.

Heterostructured oxides have shown unusual electrochemical properties including enhanced catalytic activity, ion transport, and stability. In particular, it has been shown recently that the activity of oxygen electrocatalysis on the Ruddlesden-Popper/perovskite (La1-ySry)2CoO4±δ/La1-xSrxCoO3-δ heterostructure is remarkably enhanced relative to the Ruddlesden-Popper and perovskite constituents. Here we report the first atomic-scale structure and composition of (La1-ySry)2CoO4±δ/La1-xSrxCoO3-δ grown on SrTiO3.

Joint experimental and computational 17O solid state NMR study of Brownmillerite Ba2In2O5.

Structural characterization of Brownmillerite Ba2In2O5 was achieved by an approach combining experimental solid-state NMR spectroscopy, density functional theory (DFT) energetics, and GIPAW NMR calculations. While in the previous study of Ba2In2O5 by Adler et al. (S.

Double perovskites as a family of highly active catalysts for oxygen evolution in alkaline solution.

The electronic structure of transition metal oxides governs the catalysis of many central reactions for energy storage applications such as oxygen electrocatalysis. Here we exploit the versatility of the perovskite structure to search for oxide catalysts that are both active and stable. We report double perovskites (Ln₀.

Tuning the Spin State in LaCoO Thin Films for Enhanced High-Temperature Oxygen Electrocatalysis.

The slow kinetics of oxygen surface exchange hinders the efficiency of high-temperature oxygen electrocatalytic devices such as solid oxide fuel cells and oxygen separation membranes. Systematic investigations of material properties that link to catalytic activity can aid in the rational design of highly active cathode materials. Here, we explore LaCoO thin films as a model system for tuning catalytic activity through strain-induced changes in the Co spin state.

Cation interdiffusion model for enhanced oxygen kinetics at oxide heterostructure interfaces.

An interface between the perovskite La(0.8)Sr(0.2)CoO(3-δ) (LSC-113) and the K(2)NiF(4)-type (La(0.