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Background Pulmonary hypertension (PH) is often caused by left heart disease (group 2 PH) , which is difficult to diagnose early and with a high mortality rate. Potassium channel dysfunction is a marker of PH, however, the epidemiological data of the disease and the effect of potassium ions on PH still remain unclear. Objective To investigate the correlation of serum potassium level with myocardial markers, echocardiographic indicators and length of hospital stay in patients with group 2 PH, and evaluate the predictive value of serum potassium levels for the severity of group 2 PH, so as to provide the oretical basis for clinical diagnosis and treatment. Methods The clinical data of 400 adult inpatients diagnosed with group 2 PH in the First Hospital of Shanxi Medical University from January 2020 to December 2021 were retrospectively collected as follows: (1) general data: gender, age, BMI, length of hospital stay, smoking status, smoking index (SI) and drinking history; (2) underlying diseases (diabetes mellitus, hypertension) ; (3) laboratory data: serum potassium level, myocardial markers[procalcitonin, N-terminal pro-brain natriuretic peptide (NT-proBNP) , cardiac troponin I, cardiac troponin T, creatine kinase-MB], echocardiographic indicators (left atrial diameter, right ventricular diameter, right atrial area, left ventricular ejection fraction, shortening fraction, peak tricuspid regurgitation velocity, pulmonary artery systolic pressure) . The patients were divided into 5.5 mmol/L group (n=3) according to the serum potassium level. Spearman correlation analysis was used to explore the correlation of serum potassium level with myocardial markers and echocardiographic indicators. Log-rank (Mantel-Cox) test was used to compare the discharge rate of patients with different serum potassium levels. Receiver operating characteristic curve (ROC curve) was plotted to evaluate the predictive value of serum potassium level for the severity of group 2 PH. Results Procalcitonin and NT-proBNP levels of patients in the >5.5 mmol/L group were significantly higher than the 5.5 mmol/L to investigate its relationship with length of hospital stay in depth. Log-rank (Mantel-Cox) testresults showed that for group 2 PH patients greater than average hospitalization levels, there was a significant difference in cumulative hospitalization rates among patients with different serum potassium levels (5.5 mmol/L) (P=0.022) . ROC analysis showed that the diagnostic value of serum potassium level for non-mild PH (AUC=0.577, cut-off value=3.91 mmol/L, sensitivity=64.7%, specificity=52.5%) was similar to that of NT-proBNP (AUC=0.585, cut-off value=1 070.69 pg/mL, sensitivity=78.1%, specificity=39.6%) , which can effectively predict the severity of group 2 PH. Conclusion Serum potassium level can predict the severity of group 2 PH and the length of hospital stay. Intervention of serum potassium levels may be one of the new approach to prevent and treat PH.

Flexible electronics strongly demand the integration of flexible and large‐scale multifunctional oxides. BiFeO3 is one of the most essential multifunctional oxides that could be used in memories, logics, sensors, and actuators. Recently, freestanding single‐crystalline BiFeO3 membranes exhibited superior elasticity and flexibility. However, fabrication and integration of large‐scale freestanding BiFeO3 membranes into flexible electronics remain elusive. In this study, inch‐scale freestanding single‐crystalline BiFeO3 membranes are fabricated with assistance from a water‐soluble sacrificial layer. To transfer flat and crack‐free membranes, all the existing methods are first followed but fail. Then the study introduces a temporary supporting Cu layer on the surface of the as‐grown SiTiO3/Sr3Al2O6/(SrRuO3/)BiFeO3 heterostructure and successfully obtains full and crack‐free 5 mm × 5 mm freestanding membranes on various substrates. The residual strain within the heterostructure releases gradually under the protection of the Cu layer. The freestanding BiFeO3 membranes are relatively uniform among different regions and exhibit good dielectric, ferroelectric, and ferromagnetic properties. Finally, flexible ferroelectric photovoltaic devices are patterned based on those BiFeO3 membranes, and they have open circuit voltage and short circuit current density up to −0.25 ± 0.03 V and 0.82 ± 0.09 µA cm−2, respectively. [ABSTRACT FROM AUTHOR]

Friction is a fundamental force that impacts almost all interface-related applications. Over the past decade, there is a revival in our basic understanding and practical applications of the friction. In this review, we discuss the recent progress on solid-liquid interfacial friction from the perspective of interfaces. We first discuss the fundamentals and theoretical evolution of solid-liquid interfacial friction based on both bulk interactions and molecular interactions. Then, we summarize the interfacial friction regulation strategies manifested in both natural surfaces and artificial systems, focusing on how liquid, solid, gas, and hydrodynamic coupling actions mediate interfacial friction. Next, we discuss some practical applications that are inhibited or reinforced by interfacial friction. At last, we present the challenges to further understand and regulate interfacial friction. [ABSTRACT FROM AUTHOR]

Inorganic/organic dielectric composites are very attractive for high energy density electrostatic capacitors. Usually, linear dielectric and ferroelectric materials are chosen as inorganic fillers to improve energy storage performance. Antiferroelectric (AFE) materials, especially single‐crystalline AFE oxides, have relatively high efficiency and higher density than linear dielectrics or ferroelectrics. However, adding single‐crystalline AFE oxides into polymers to construct composite with improved energy storage performance remains elusive. In this study, high‐quality freestanding single‐crystalline PbZrO3 membranes are obtained by a water‐soluble sacrificial layer method. They exhibit classic AFE behavior and then 2D–2D type PbZrO3/PVDF composites with the different film thicknesses of PbZrO3 (0.1‐0.4 µm) is constructed. Their dielectric properties and polarization response improve significantly as compared to pure PVDF and are optimized in the PbZrO3(0.3 µm)/PVDF composite. Consequently, a record‐high energy density of 43.3 J cm−3 is achieved at a large breakdown strength of 750 MV m−1. Phase‐field simulation indicates that inserting PbZrO3 membranes effectively reduces the breakdown path. Single‐crystalline AFE oxide membranes will be useful fillers for composite‐based high‐power capacitors. [ABSTRACT FROM AUTHOR]

Ferroelectric memory is one of the most attractive emerging nonvolatile memory. Conventional methods to increase storage density in ferroelectrics include reducing the storage bit size or fabricating 3D stacks. However, the former will face a physical limit finally, and the integration of single‐crystalline ferroelectric oxide following the latter still remains a great challenge. Here, a new method is introduced to construct a scroll‐like 3D memory structure by self‐rolling‐up single‐crystalline ferroelectric oxides. PbZr0.3Ti0.7O3 single‐crystalline thin film is chosen as a prototype and epitaxially grown on another oxide stressor layer with a few lattice‐mismatch. Releasing such "Pb(Zr, Ti)O3/stressor" bilayered structure from the substrate induces self‐rolling‐up due to the internal stress from the lattice‐mismatch. High‐density information can be written in the form of switched ferroelectric domains on those flat "Pb(Zr, Ti)O3/stressor" membranes via piezoelectric force microscopy. In self‐rolling‐up membranes, information density can be experimentally enhanced up to 45 times. Theoretically, the freestanding "Pb(Zr, Ti)O3/stressor" membranes have a strongly driven force to self‐rolling‐up, and the area ratio can enhance 100–450 times, corresponding to an ultra‐high density information storage of 102 Tbit In−2. This study provides a new and general method to develop compact, high‐density, and 3D memories from oxide materials. [ABSTRACT FROM AUTHOR]

Belitic calcium sulfoaluminate (BCSA) cement-based mixtures are suitable for permafrost region applications due to their fast strength development. To better understand their performance and guide future applications, this study aimed to develop a numerical model for predicting the temperature profiles in BCSA cement-based mixtures used in permafrost regions. Isothermal calorimetry and the Arrhenius equation were used to determine the heat generation rate of BCSA cement. The modeling of temperature profiles in BCSA cement-based mixtures was implemented with a finite element model, which was validated with experimental results. In the model, the temperature profiles in BCSA cement-based samples cured in cold sand (0 °C, −5 °C and −10 °C) to mimic the influence of permafrost environments, and another group was cured in cold air at the same temperatures. The results indicate that the developed numerical model can accurately predict the temperature profiles in hardening BCSA cement-based mixtures for permafrost region applications (root mean square error ≤ 1.3 °C). The modeling results provided valuable guidance to future research and practical applications of BCSA cement-based mixtures in permafrost regions. First, samples should be cured in cold soil or sand when investigating the performance of BCSA cement-based materials used in permafrost regions because the temperature in samples cured in sand was notably (e.g. 28 °C) lower than that of the same mixture cured in air. Second, precautions are needed to control thermal cracks when BCSA cement-based mixtures are used in cold temperatures because the temperature gradient (e.g. 45 °C) in the BCSA cement-based sample was high even if the sample size was small (e.g. Ø300 × 600mm). [ABSTRACT FROM AUTHOR]

Magnesium alloys are ideal materials in clinical applications for their excellent mechanical properties, while potential cytotoxicity with rapid degradation limits their clinical applications. Moreover, it is also important for implants to avoid inflammation caused by bacterial infections in the early stage of implantation. Therefore, copper-doped anhydrous calcium phosphate nanoparticles were fabricated by the hydrothermal method and dispersed in a dicalcium phosphate dihydrate (DCPD)/Polycaprolactone (PCL) composite coating to improve its bacteriostatic properties, corrosion resistance, and biocompatibility in this paper. The impedance of the DCPD/PCL/Cu-doped anhydrous calcium phosphate (Cu-ADCP) composite-coated sample is 1 order of magnitude higher than that of the bare magnesium alloy, and the corrosion current density decreases by 2 orders of magnitude, indicating that the composite coating incorporating nanoparticles can effectively enhance the corrosion resistance. The in vitro cell experiments show its biocompatibility with sustained growth in cellular activity and increased alkaline phosphatase activity. Most importantly, the embedded copper-doped nanoparticles significantly improve the antibacterial properties of the composite coating. Compared with the composite coating with almost no antibacterial ability, the antibacterial rate reached 96 and 98% for Escherichia coli and Staphylococcus aureus , respectively, after the nanoparticles were embedded, making them a promising choice for orthopedic applications. [ABSTRACT FROM AUTHOR]

Selective laser melting of nickel‐titanium alloy (SLM‐NiTi) can precisely control the size of the sample molding structure and has attracted extensive attention due to its special superelasticity and shape memory effect. However, the biological inertness and poor corrosion resistance of SLM‐NiTi alloy limit their wide application as biomedical implant materials. In this study, polycaprolactone (PCL) coating was prepared on SLM‐NiTi alloy by dipping and pulling method, and the effects of alkali heat pretreatment on the morphology, adhesion, corrosion resistance, long‐term stability and biomineralisation of the PCL coatings were investigated. The results showed that PCL coating can substantially improve the performance of SLM‐NiTi alloy, and the PCL coating after alkali heat pretreatment has higher adhesion (increased from 1,747 to 2,498 mN) and lower corrosion current density (reduced by about an order of magnitude compared to PCL coating alone). In addition, the necessary stability, biomineralisation and biocompatibility ability of coatings were also further improved. Therefore, the alkali heat pretreated PCL‐coated SLM‐NiTi alloy has good application prospects in implants due to its superior properties. [ABSTRACT FROM AUTHOR]