Single-Crystal P2-Na0.67Mn0.67Ni0.33O2 Cathode Material with Improved Cycling Stability for Sodium-Ion Batteries.

Layered oxides constitute one of the most promising cathode materials classes for large-scale sodium-ion batteries because of their high specific capacity, scalable synthesis, and low cost. However, their practical use is limited by their low energy density, physicochemical instability, and poor cycling stability. Aiming to mitigate these shortcomings, in this work, we synthesized polycrystalline (PC) and single-crystal (SC) P2-type Na0.67-δMn0.67Ni0.33O2 (NMNO) cathode materials through a solid-state route and evaluated their physicochemical and electrochemical performance. The SC-NMNO cathode with a large mean primary particle size (D50) of 12.7 µm was found to exhibit high cycling stability leading to 47% higher capacity retention than PC-NMNO after 175 cycles at 1C rate in the potential window 4.2-1.5 V. This could be attributed to the effective mitigation of parasitic side reactions at the electrode-electrolyte interface and suppressed intergranular cracking induced by anisotropic volume changes. This is confirmed by the lower volume variation of SC-NMNO (ΔV ∼ 1.0%) compared to PC-NMNO (ΔV ∼ 1.4%) upon charging to 4.2 V. Additionally, the SC-NMNO cathode displayed slightly higher thermal stability compared to PC-NMNO. Both cathodes exhibited good chemical stability against air and water exposure, thus enabling material storage/handling in the ambient atmosphere as well as making them suitable for aqueous processing. In this regard, PC-NMNO was investigated with two low-cost aqueous binders, carboxymethyl cellulose, and sodium trimetaphosphate, which exhibited higher binding strength and displayed excellent electrochemical performance compared to PVDF, which could potentially lead to significant cost reduction in electrode manufacturing.

Three-Dimensional Nitrogen-Doped Carbonaceous Networks Anchored with Cobalt as Separator Modification Layers for Low-Polarization and Long-Lifespan Aluminum-Sulfur Batteries.

Aluminum-sulfur (Al-S) batteries have attracted extensive interest due to their high theoretical energy density, inherent safety, and low cost. However, severe polarization and poor cycling performance significantly limit the development of Al-S batteries. Herein, three-dimensional (3D) nitrogen-doped carbonaceous networks anchored with cobalt (Co@CMel-ZIF) is proposed as a separator modification layer to mitigate these issues, prepared via carbonizations of a mixture of ZIF-7, melamine, and CoCl2. It exhibits a 3D network structure with a moderate surface area and high average pore diameter, which is demonstrated to be effective in adsorbing the aluminum polysulfides and hindering the mobility of polysulfides across the separator for enhanced cyclic stability of Al-S batteries. Meanwhile, Co@CMel-ZIF are characterized by abundant catalytic pyridinic-N and Co-Nx active sites that effectively eliminate the barrier of sulfides' conversion and thereby facilitate the polarization reduction. As a result, Al-S cells based on the separator modified with Co@CMel-ZIF exhibit a low voltage polarization of 0.47 V under the current density of 50 mA g-1 at 20 °C and a high discharge specific capacity of 503 mAh g-1 after 150 cycles. In contrast, the cell employing a bare separator exhibits a polarization of 1.01 V and a discharge capacity of 300 mAh g-1 after 70 cycles under the same conditions. This work demonstrates that modifying the separators is a promising strategy to mitigate the high polarization and poor cyclability of Al-S batteries.

The interaction of O-GlcNAc-modified NLRX1 and IKK-α modulates IL-1ß expression in M1 macrophages.

NOD-like receptor (NLR)X1 (NLRX1) is a negative regulator of inflammation by inhibiting nuclear factor-κB (NF-κB) signaling and downstream pro-inflammatory factors. However, its post-translational modification and how it participates in regulating the inflammatory responses in macrophages are still unclear. Here, we found that NLRX1 was modified with O-linked N-acetylglucosamine (O-GlcNAc). The interaction and co-localization between NLRX1 and O-GlcNAc transferase (OGT) was validated by co-immunoprecipitation and confocal microscopy analysis, and the nucleotide-binding domain (NBD) region of NLRX1 was required for its interaction with OGT. NLRX1 protein increased significantly after treatment with a high dose of OGT inhibitor OSMI-1. Elevated O-GlcNAcylation level promoted NLRX1 ubiquitination and decreased NLRX1 stability proved by ubiquitination and cycloheximide (CHX) chase experiments, and enhanced the interaction between NLRX1 and inhibitor of nuclear factor kappaB kinase-α (IKK-α), thus reducing the expression of inflammatory cytokine IL-1ß in M1 macrophages. Together, our results indicate that the interaction between NLRX1 and O-GlcNAcylation coordinates and modulates the inflammatory process in macrophages.

Case Report: A Case of Unusual Combination of Hypothyroidism, Myocardial Bridging, and Myocardial Infarction-Induced Left Ventricular Aneurysm.

Background: Myocardial bridging (MB) of the coronary artery is a congenital anatomical variation, which has traditionally been considered a benign condition that does not cause cardiovascular events. However, recent studies have shown that MB is associated with major adverse cardiac events, including angina, myocardial infarction, arrhythmia, syncope, and even sudden death. Case: We report a case of a 41-year-old man who had hypothyroidism and MB associated with ventricular aneurysm following myocardial infarction. This patient was admitted to our hospital because of 11 days of sudden discomfort and pain in the chest. An electrocardiogram on admission showed an old myocardial infarction. Coronary angiography showed MB in the distal segment of the left anterior descending artery. Left ventricular angiography, which was performed using a pigtail catheter, showed ventricular aneurysm formation. Thyroid ultrasound demonstrated hypothyroidism and Hashimoto's thyroiditis. Patients with hypothyroidism and MB have a high risk of acute myocardial infarction or even sudden death. Conclusion: Observations in our case suggest that early recognition of hypothyroidism and MB is important for risk stratification and prognosis in patients with myocardial necrosis and acute coronary syndrome. Additionally, this early recognition may have positive effects on cardiovascular outcomes in patients with hypothyroidism.

Enhanced Potassium Storage Capability of Two-Dimensional Transition-Metal Chalcogenides Enabled by a Collective Strategy.

Potassium-ion batteries (PIBs) have been considered as a promising alternative to lithium-ion batteries due to their merits of high safety and low cost. Two-dimensional transition-metal chalcogenides (2D TMCs) with high theoretical specific capacities and unique layered structures have been proven to be amenable materials for PIB anodes. However, some intrinsic properties including severe stacking and unsatisfactory conductivity restrict their electrochemical performance, especially rate capability. Herein, we prepared a heterostructure of high-crystallized ultrathin MoSe2 nanosheet-coated multiwall carbon nanotubes and investigated its electrochemical properties with a view to demonstrating the enhancement of a collective strategy for K storage of 2D TMCs. In such a heterostructure, the constructive contribution of CNTs not only suppresses the restacking of MoSe2 nanosheets but also accelerates electron transport. Meanwhile, the MoSe2 nanosheets loaded on CNTs exhibit an ultrathin feature, which can expose abundant active sites for the electrochemical reaction and shorten K+ diffusion length. Therefore, the synergistic effect between ultrathin MoSe2 and CNTs endows the resulting nanocomposite with superior structural and electrochemical properties. Additionally, the high crystallinity of the MoSe2 nanosheets further leads to the improvement of electrochemical performance. The composite electrode delivers high-rate capacities of 209.7 and 186.1 mAh g-1 at high current densities of 5.0 and 10.0 A g-1, respectively.

In-situ formation and evolution of atomic defects in monolayer WSe2 under electron irradiation.

Transition metal dichalcogenide (TMD) monolayers such as MoS2, MoSe2, MoTe2, WS2 and WSe2 have attracted significant interest due to their remarkable electronic and optical properties, exhibiting a direct band gap, enabling usability in electronics and optics. Their properties can be altered further by the introduction of lattice defects. In this work, the dynamics of the formation of electron-beam-induced lattice defects in monolayer WSe2 are investigated by in-situ spherical and chromatic aberration-corrected low-voltage transmission electron microscopy. We show and analyze the electron-dose-limited life of a monolayer WSe2 from the formation of isolated Se vacancies over extended defects such as vacancy lines, mirror twin boundaries (MTBs) and inversion domains towards the loss of W atoms leading to the formation of holes and finally the destruction of the monolayer. We identify, moreover, a new type of MTB. Our study extends the basic understanding of defect dynamics in monolayer WSe2, sheds further light on the electron radiation response and suggests new ways for engineering the in-plane architecture of TMDs.

Rheumatic valvular heart disease combined with woven coronary artery: a case report.

BACKGROUND: Woven coronary artery (WCA) is an extremely rare congenital anomaly in which a part of epicardial coronary artery is divided into thin channels, that twist along the axis of the coronary arteries and then merge again as the main coronary lumen. This anomaly is regarded as a benign condition because the blood flow is normal. Very few cases of WCA have been reported. CASE PRESENTATION: Herein we report a case of a 44-year-old man who was admitted to our hospital due to 20 years of repeated episodes of heart palpitations, 2 years of shortness of breath after activity, and the symptoms were aggravated for 1 month. He had history of inferior myocardial infarction and atrial fibrillation. Color Doppler echocardiography revealed rheumatic heart disease, severe mitral regurgitation, mild-moderate tricuspid regurgitation, moderate pulmonary hypertension. Coronary angiography revealed 60-85% diffuse stenosis in the middle of left anterior descending artery, 60-90% diffuse stenosis in the middle of left circumflex artery, 30-40% diffuse stenosis in the proximal segment of right coronary artery, and WCA anomaly in the middle, and distal segments of right coronary artery. CONCLUSION: The patient successfully underwent prosthetic valve replacement and left anterior descending coronary artery bypass grafting, and had a good recovery after surgery. Further studies are needed to fully understand the disease and determine appropriate treatment options.

Dilated cardiomyopathy and aldosteronoma: a causal link?

The aim of this study is to reveal the causal relationship between dilated cardiomyopathy and aldosteronoma. A 44-year-old male dilated cardiomyopathy patient with aldosteronoma, who demonstrated a worse cardiac function after 1 year therapy with optimized dosage of sacubirtil/valsartan, furosemide, metoprolol, and spironolactone. The patient shows a promising prognosis after aldosteronoma removal procedure. Aldosteronoma may cause dilated cardiomyopathy. We assume that the optimal treatment for aldosteronoma-induced dilated cardiomyopathy is surgical removal combined with drugs.

Applying WCACG modified process is beneficial on reduced door-to-balloon time of acute STEMI patients.

BACKGROUND: Various systems have employed with the objective to reduce the time from emergency medical services contact to balloon inflammation for ST-elevation myocardial infraction (STEMI) patients. The WCACG message system was used to an alternative communication platform to improve confirmation of the diagnosis and movement to treatment, resulted in shorten the door-to-balloon (D-to-B) time for STEMI patients. METHODS: We collected 366 STEMI patients admitted at the Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Department of Cardiology, during the period from June 2013 to October 2015. The patients were divided into two groups one underwent the current GC processes and the other group was handled using WCACG system. We compared between two groups with several indicators including D-to-B time, duration of hospitalization, associated costs, and incidence of adverse cardiovascular events. RESULTS: The results show that the new method with WCACG system significantly reduced the average D-to-B time (from 100.42 ± 25.14 mins to 79.81 ± 20.51 mins, P < 0.05) compared to the GC processes, and also reduced the duration, costs and undesirable cardiac incidence during hospitalization. CONCLUSIONS: The modified WCACG process is an applicable system to save pieces of time and efficiently integrate the opinions of experts in emergency.

Enhancing potassium-ion battery performance by defect and interlayer engineering.

Defect and interlayer engineering is applied to exploit the large van der Waals gaps of transition metal dichalcogenides for potassium-ion batteries (KIBs). As a demonstrator, MoS2 nanoflowers with expanded interlayer spacing and defects in the basal planes are used as KIB anodes in the voltage range of 0.5-2.5 V, where an intercalation reaction rather than a conversion reaction takes place to store K-ions in the van der Waals gaps. The nanoflowers show enhanced K-storage performance compared to the defect-free counterpart that has a pristine interlayer spacing. Kinetic analysis verifies that the K-ion diffusion coefficient and surface charge storage are both enhanced in the applied voltage range of the intercalation reaction. The collective effects of expanded interlayer spacing and additionally exposed edges induced by the in-plane defects enable facile K-ion intercalation, rapid K-ion transport and promoted surface K-ion adsorption simultaneously.

Competing Interfacial Reconstruction Mechanisms in La0.7Sr0.3MnO3/SrTiO3 Heterostructures.

Interface coupling between complex oxides offers unique possibilities to tailor materials properties and stabilize novel ground states. Understanding the structural reconstruction of the corner-shared octahedral framework and the charge redistribution are crucial for controlling interfacial properties in oxide electronics. Here, we study the interfacial oxygen octahedral behavior in La0.7Sr0.3MnO3/SrTiO3 heterostructure, by directly imaging the oxygen octahedra at the atomic scale and extracting the structural parameters. We combine these experimental results with electronic structure calculations to elucidate the effect of reconstructed MnO6 octahedral geometry on increased interfacial magnetization and conductivity. The Mn valence profiles near the interface are quantitatively analyzed and compared at variant temperatures, revealing the insulating nature of interfacial manganite with reduced Mn valence. This study suggests a pathway to manipulate the interfacial properties and creation of new ground states in complex oxide heterostructures by tuning competing structural and electronic parameters.

Atomic structure and polarity compensation of BaTiO3 (1 1 1) surface.

Surfaces of perovskite-type oxides have been attracting increasing interest for their primary importance in various potential applications such as multiferroic thin films, interface electronics and catalysis. However, the (1 1 1) surface of BaTiO3, the most typical ferroelectric, is far from well understood. In this work, the atomic structure and polarity compensation of BaTiO3 (1 1 1) surface have been investigated combining aberration-corrected transmission electron microscopy and first-principle calculations. Depending on the density of oxygen vacancies, the surface shows different degrees of atomic relaxation and electronic charge transfer, which compensates the surface polarity together with the ionic charges associated with the oxygen vacancies. The atomic relaxation and charge transfer would have a direct impact on the ferroelectric and catalytic properties of low-dimensional BaTiO3.