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Background. Endothelial barrier disruption of human pulmonary vascular endothelial cells (HPVECs) is an important pathogenic factor for acute lung injury (ALI)/acute respiratory distress syndrome (ARDS). Mesenchymal stem cells-exosome (MSCs-Exo) represents an ideal carrier for cell-free therapy. The therapeutic implication and underlying mechanism of human placental MSCs-Exo (HPMSCs-Exo) in ALI/ARDS need to be further explored. Materials and Methods. HPMSCs-Exo was extracted from HPMSCs and characterized. Then, the therapeutic effects of exosomes were evaluated in ALI mice and HPVECs. RNA-sequencing was applied to reveal the miRNA profile of HPMSCs-Exo and differentially expressed genes (DEGs) in HPMSCs-Exo-pretreated HPVECs. The targets of miRNAs were predicted by bioinformatics methods and correlated to DEGs. Finally, the role of hsa-miR-148a-3p/ROCK1 pathway in HPVECs has been further discussed. Results. The results showed that HPMSCs-Exo could downregulate Rho-associated coiled-coil-containing protein kinase 1 (ROCK1), upregulate the expression of zonula occludens-1 (ZO-1) and F-actin, promote HPVECs migration and tube formation, reduce cytoskeletal disorders and cell permeability, and thus improve ALI/ARDS. RNA-sequencing revealed the DEGs were mainly enriched in cell junction, angiogenesis, inflammation, and energy metabolism. HPMSCs-Exo contains multiple miRNAs which are associated with cytoskeletal function; the expression abundance of hsa-miR-148a-3p is the highest. Bioinformatic analysis identified ROCK1 as a target of hsa-miR-148a-3p. The overexpression of hsa-miR-148a-3p in HPMSCs-Exo promoted the migration and tube formation of HPVECs and reduced ROCK1 expression. However, the overexpression of ROCK1 on HPVECs reduced the therapeutic effect of HPMSCs-Exo. Conclusions. HPMSCs-Exo represents a protective regimen against endothelial barrier disruption of HPVECs in ALI/ARDS, and the hsa-miR-148a-3p/ROCK1 pathway plays an important role in this therapeutics implication. [ABSTRACT FROM AUTHOR]

Objective: The objective of this study was to examine the predictive ability of follicle‐stimulating hormone (FSH)/luteinizing hormone (LH) ratio and antimullerian hormone (AMH) levels in the same cohort when both are inconsistent and to identify which has an excellent ability to predict live birth and ovarian response to in vitro fertilization (IVF). Methods: A retrospective cohort study was performed within 6096 IVF cycles executed between January 2016 and August 2019 at the Center for Assisted Reproduction, The Third Affiliated Hospital of Zhengzhou University, and Jiaozuo Maternity and Child Health Care Hospital. Initially, IVF cycles were classified according to basal FSH/LH ratio and AMH values, and the primary outcome was a comparison of live birth rate per cohort. Secondary outcomes included characteristics of the study individuals such as body mass index (BMI), age, antral follicle count, ovarian sensitivity index, cycle cancellation rate, and cycle outcome data. Result(s): Women with FSH/LHhigh ratio and AMHnormal levels had a meaningly higher live birth rate compared with those with FSH/LHnormal ratio and AMHlow levels (46.59% vs. 21.21%, p < 0.001). In addition, women with FSH/LHnormal ratio and AMHlow levels were found to have a higher cancellation rate in their IVF cycles (80.98%). In women with FSH/LHnormal ratio, further multivariate analysis revealed that AMH level, age, number of retrieved oocytes, and FSH dosage were relevant risk factors for live birth. The relative risk of live birth was 0.11 (95% [CI] 0.06–0.20, p < 0.001) in patients with AMHlow compared with patients with AMHnormal. It also suggested that the probability of AMHlow level may be higher as the women's age (≥35 years, odd ratio [OR] 1.94, 95% [CI] 1.44–2.61; p < 0.001) and increasing BMI (≥28 kg/m2, OR 2.38, 95% [CI] 1.33–4.27; p = 0.004). Receiver operating characteristic curve analysis indicated that AMH had higher sensitivity and specificity to predict live birth compared with FSH/LH (AUC 0.627 vs. 0.539). Conclusion(s): AMH levels can be an excellent predictor of the discrepancy between FSH/LH ratio and AMH levels regarding living birth rates in women undergoing IVF. [ABSTRACT FROM AUTHOR]

Dolostone reservoirs are crucial for global oil and gas storage, holding a significant portion of hydrocarbon reserves within carbonate formations. Understanding the chemical mechanism of dolomite dissolution with organic acids and associated porosity development in these reservoirs is vital for optimizing hydrocarbon recovery. In this work, two sets of simulation experiments are designed to understand the controls of temperature and ionic effects on porosity enhancement during the dissolution of dolomite with acetic acid. In specific, we discovered a three-step reaction process between dolomite and acetic acid, involving acetic acid dissolution in water, acetic acid dissociation, and dolomite dissolution. Burial environments with higher temperatures reduce the degree of acetic acid dissociation, leading to a corresponding decrease in dolomite dissolution in acetic acid solutions. The presence of salt ions in the solution influences the reaction process, with magnesium chloride (MgCl 2) having the most significant enhancing effect on dolomite dissolution, followed by sodium chloride (NaCl), while calcium chloride (CaCl 2) has a limited impact. Sodium sulfate (Na 2 SO 4) enhances dolomite dissolution at lower temperatures; however, at higher temperatures (>100 °C), it may reduce dolomite dissolution due to the precipitation of CaSO 4. Despite a relatively short open-flow time, episodic burial dissolution of dolomite by acetic acid fluids under overburden pressure leads to a "net increase" in the reservoir space and enhances its connectivity attributes. During burial diagenesis, geological forces episodically drive organic acid fluids to the dolomite reservoir, predominantly dissolving dolomite along pre-existing pore development zones and geological interfaces, exhibiting inheritance, episodicity, and localization characteristics. Overall, this study provides insights into the dissolution and diagenetic processes of dolomite in the presence under acetic acids, from the point of dissolution simulation experiments. Collectively, these findings enhance our understanding of pore-system evolution and fluid-rock interactions in deep carbonate reservoirs. • Simulations reveal temperature and ions' effects on dolomite porosity in acetic acid. • Higher temperatures reduce acetic acid dissociation and dolomite dissolution. • Nonlinear response of dolomite dissolution under Na 2 SO 4 -contained acid with temperature. • Episodic acetic acid-dolomite dissolution enhances reservoir space and connection. [ABSTRACT FROM AUTHOR]

TiO2 nanoparticles can improve the electrical performance of oil paper insulation. In this study, 10 nm TiO2 nanoparticles were prepared and dispersed into transformer oil, and then immerse pressboards in it to obtain nanofluid impregnated pressboards (NP). Its thermal aging was accelerated together with the reference sample at 130°C for 36 days. Analyzing the acid value in the oil, polymerization degree, surface topography, AC breakdown strength, surface flashover characteristics and surface potential decay characteristics. It was observed that TiO2 nanoparticles can reduce the acid value and improve AC breakdown strength of oil. However, the degree of polymerization and surface appearance of NP and oil impregnated pressboards (OP) during thermal aging did not differ significantly. During the aging process, the energy level of pressboard surface traps shifted first towards the shallow and then gradually towards the deep. During all the aging stages, the surface flashover voltage of NP was always higher or close to that of OP. The mechanism of TiO2 nanoparticles improving the breakdown and surface flashover characteristics of oil–paper insulation during thermal aging is discussed from the perspective of water molecules and aging by‐products adsorption and introduction of shallow traps by nanoparticles. [ABSTRACT FROM AUTHOR]

The phenolic adhesive and casein adhesive are two kinds of adhesives used in pressboard block production. The partial discharge characteristics of pressboard block containing the two types of adhesives under AC, DC and AC/DC composite voltage are researched in this paper. Using the block samples with phenolic adhesive or casein adhesive, the partial discharge characteristics, flashover characteristics and the influence of the adhesive layer orientations were obtained. The results show that the use of adhesive may introduce a weak zone of insulation performance and reduce the insulation strength of the pressboard block. There exist polar effects on partial discharge and flashover characteristics under DC voltage, and there is no significant difference in the partial discharge characteristics and flashover voltages between the pressboard blocks with casein and phenolic adhesive. The phenomena are analyzed in terms of molecular characteristics of adhesives and cellulose pressboard. The research results of this paper provide significant theoretical and practical reference for the optimization of transformer insulation materials. [ABSTRACT FROM AUTHOR]

Four-electron process and the interference of Cl- make sluggish kinetics on oxygen evolution reaction (OER) for seawater electrolysis. Herein, NiFe LDH grown on NiFe-foam with CeO 2 modification and (W 2 O 7)2- intercalation was synthesized by one-step hydrothermal method. It only needs 353.8 and 386.7 mV to achieve a large current density of 1000 mA·cm−2 in 1 M KOH and alkaline natural seawater, respectively. The catalytic material can stand 100 h with a retention of 98.1% at 1000 mA·cm−2 in alkaline natural seawater. Experiments and theoretical calculations confirm that the state-of-the-art OER activity comes from the introduced CeO 2 with optimized adsorption energy of intermediates. The improved stability and selectivity in seawater can be ascribed to the preferential adsorption of Ni and Fe with higher valence on OH- based on hard and soft acid based (HSAB) principle by (W 2 O 7)2- intercalation. This work provides a viable approach to develop efficient catalytic material for large-current seawater electrolysis. NiFe LDH nanosheets with (W 2 O 7)2- intercalation and CeO 2 modification show state-of-the-art large-current seawater-electrooxidation performance contributed partially from introduced CeO 2 adjusting adsorption energy of intermediates during OER process, partially from preferential adsorption of OH- on metal active sites based on hard and soft acid based (HSAB) principle by (W 2 O 7)2- intercalation. [Display omitted] • NiFe LDH nanosheets with (W 2 O 7)2- intercalation and CeO 2 modification have been successfully synthesized. • It only needs an overpotential of 386.7 mV to achieve 1000 mA cm−2 in alkaline natural seawater electrocatalysis. • (W 2 O 7)2- intercalation enhances OH- selectivity and CeO 2 modification optimizes adsorption energy towards OER intermediates. [ABSTRACT FROM AUTHOR]

[Display omitted] • Compositional regulation by introducing MoS 2 provides rich H adsorption sites. • Internal electronic regulation in heterostructure accelerates the RDS in OER process. • MnCo 2 S 4 @MoS 2 employed as a bifunctional catalyst for efficient hydrogen production. • Operating stably in industrial condition with structural reconstruction at the anode. • The electron redistribution and reaction pathways are explained by DFT calculations. It remains to be challenging to develop bifunctional catalysts for overall water splitting (OWS) with high activity and durability at large current density. In an attempt to overcome this bottleneck, unique MnCo 2 S 4 hexagonal stars covered with MoS 2 nanosheets were in-situ grown on nickel foam (NF) to obtain MnCo 2 S 4 @MoS 2 /NF heterostructure with optimized composition and local electronic structure in this work. When employed as a bifunctional catalyst, it only needs low overpotentials of 208 and 332 mV in 6.0 M KOH to drive 1000 mA cm−2 with small Tafel slopes of 56.8 and 75.6 mV dec-1 for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), respectively. In addition, MnCo 2 S 4 @MoS 2 /NF showed remarkable stability in simulated industrial conditions, operating stably for 50 h at 1000 mA cm−2 without any attenuation for HER/OER. Thus, the MnCo 2 S 4 @MoS 2 /NF can function as a bifunctional electrocatalyst for OWS, only requiring 1.795 V to afford 1000 mA cm−2 with splendid stability. The improved performance is ascribed to dual electric and compositional regulation, which endow MnCo 2 S 4 @MoS 2 /NF with rich active sites and heterointerfaces, thereby promoting electron transfer and boosting the reaction kinetic. Furthermore, density functional theory (DFT) calculations reveal that the construction of heterostructure can help regulate intrinsic electronic structure, resulting in accelerated reaction kinetics. This work provides a reasonable and meaningful method for boosting industrial green hydrogen production. [ABSTRACT FROM AUTHOR]

The relationship between the permittivity of a two-phase porous composite material and its structure forms the basis for the adjustment and analysis of the permittivity of the porous material. However, existing calculation models exhibit significant errors at low frequencies. A wide-frequency equivalent model is proposed in this paper based on the geometrical structural characteristics of porous materials, considering the effects of interface polarization and dielectric relaxation process. The relationship between the two-phase porosity material and the dielectric response of its framework and filling medium in a wide-frequency range can be calculated. Furthermore, the modified Cole–Cole model is adopted to analyze the dielectric spectrum characteristics of cellulose and aramid, thereby exhibiting the effects of polar bonds in the molecular structure and impurity ions in the material on the polarization strength and polarization process. The results obtained from this study can provide key parameters and a basis for the analysis of the polarization process of two-phase combined porous materials and the design of low-permittivity insulating paper. [Display omitted] [ABSTRACT FROM AUTHOR]

Low-temperature preparation of efficient electron transport layer (ETL) can effectively expand the application of perovskite solar cells (PSCs). We herein introduce anatase TiO 2 nanoparticles (NPs) with an average diameter of 15 nm prepared by hydrothermal method and optimized with acetic acid (AA) as well as oleic acid (OA). The Ti3+ as well as Ti–OH signals indicate the surface defects of TiO 2 NPs investigated by X-ray photoelectron spectroscopic (XPS) are observed to be passivated by the modifiers through chelate or bridging pattern. Thus, when the modified NPs are dispersed into the precursor for spin-coating ETLs under 150 °C, higher power conversion efficiency (PCE) of 20.15% and 19.41% is achieved based on planar structured PSC using TiO 2 modified with AA and OA, respectively. The device stability is also considerably increased. Analyzed by photoluminescence and electrochemical impedance spectroscopies, the improved cell performance can be ascribed to the reduced charge transport resistance, enhanced electron extraction, and suppressed recombination behavior. We anticipate this facile approach of fabricating efficient TiO 2 ETLs can be further employed into PSCs commercialization. [ABSTRACT FROM AUTHOR]