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Objective: This clinical trial was performed to evaluate the effect of nasal tube stabilization (NTS) on the pressure between tube and nose (PTN) in both supine and neck extension positions.Study Design: This prospective randomized controlled trial recruited 24 American Society of Anesthesiologists physical status I or II adult patients who underwent oral and maxillofacial surgeries requiring nasotracheal intubation. Patients were randomly assigned to intubate with either wire-reinforced or RAE (Ring-Adair-Elwyn) tube. A thin-film pressure sensor was used to measure PTN before and after NTS in both supine and neck extension positions. Statistical analysis was performed with the GraphPad Prism 9.0 software package.Results: The PTN of wire-reinforced tubes was 51 mmHg higher than that of RAE tubes in supine position before NTS (P = .005). In the wire-reinforced tube group before NTS, neck extension position increased the PTN compared with supine position (P = .0005). After NTS, the PTN in supine and neck extension positions was comparable (P = .1514). NTS significantly reduced PTN in both supine (P = .0005) and extension positions (P = .0005). In the RAE tube group, the PTN in supine and neck extension positions was comparable, either before (P = .3394) or after NTS (P = .7910). NTS also significantly reduced PTN in both supine (P = .0005) and extension positions (P = .0005).Conclusions: NTS effectively reduced the PTN of both wire-reinforced and RAE tubes, regardless of the supine or neck extension position. RAE tubes also significantly reduced the PTN compared with wire-reinforced tubes. [ABSTRACT FROM AUTHOR]

Background Alcohol-induced hangover represents a significant, yet understudied, global hazard and a large socioeconomic burden. Objective The aim of this study was to investigate the effects of hydrogen on relieving drinking and hangover symptoms in 20 healthy volunteers. Methods In this pilot, randomized, double-blinded, placebo-controlled, matched, crossover interventional trial, participants were matched into pairs and randomly assigned. Study group 1 inhaled placebo air for 1 h, followed by drinking 100 mL liquor (40% alcohol) within 10 min, and then pure water. Study group 2 inhaled a mixture of hydrogen and oxygen gas for 1 h, followed by drinking 100 mL liquor within 10 min, and then hydrogen dissolved in water. On a second intervention day (crossover) ≥1 wk later, study-group subjects were switched to the opposite order. Breath alcohol concentration (BrAC), hangover severity, and cognitive scores were measured. Results The BrACs within the hydrogen group were significantly lower than those within the placebo group after 30 min, 60 min, and 90 min (P   <  0.05). The hydrogen group reported having fewer hangover symptoms compared with the placebo group (placebo: 77% of symptoms absent, 19.7% of mild symptoms, 2.7% of moderate symptoms, 0.7% of severe symptoms; hydrogen: 88.6% of symptoms absent, 10% of mild symptoms, 1.3% of moderate symptoms, 0% of severe symptoms; P   <  0.001). Hydrogen treatment improved cognitive testing scores (P   <  0.05), including attention and executive functions. Furthermore, consumption of hydrogen was negatively (β = −13.016; 95% CI: −17.726, −8.305; P   <  0.001) and female sex was positively (β = 22.611; 95% CI: 16.226, 28.997; P   <  0.001) correlated with increased BrACs. Likewise, the consumption of hydrogen was negatively (OR: 0.035; 95% CI: 0.007, 0.168; P   <  0.001) while female sex was positively (OR: 28.838; 95% CI: 5.961, 139.506; P   <  0.001) correlated with the severity of hangover symptoms. Conclusions Hydrogen decreases BrACs and relieves the symptoms of hangovers. This trial was registered at the China Clinical Trial Registry (http://www.chictr.org.cn/showproj.aspx?proj=58359) as ChiCTR2200059988. [ABSTRACT FROM AUTHOR]

Carbide dispersion for reinforcement is an effective strategy to enhance the performance of tungsten (W). High-entropy carbides (HECs), when compared to conventional carbides, offer superior thermal stability, hardness, mechanical strength, creep resistance, and wear resistance. This study represents the first successful incorporation of (HfNbTaZr)C as a reinforcing phase into a W matrix, resulting in the formation of a W-HEC alloy. Compared to other carbides such as ZrC, HEC demonstrates improved coherency with the W matrix, resulting in a significant increase in plasticity and enhanced high-temperature stability. This innovative approach paves the way for alloy design in high-temperature applications such as nuclear fusion, providing fresh insights into the enhancement of mechanical properties and thermal stability. • A (HfNbTaZr)C HEC has been synthesized, for the first time, incorporated as a reinforcing phase into the W matrix. • The mismatch between HEC(200) and W(110) is 0.018, smaller than the W-ZrC alloy, indicating better coherence with the W matrix. • The W-HEC demonstrates outstanding plasticity at 600 °C, displaying total elongation of 33.0%, surpassing other W alloys. • The W-HEC hardness decreases is less than the W-ZrC after annealing at 1800 °C, demonstrating superior thermal stability. [ABSTRACT FROM AUTHOR]

By studying the alone and synergetic effects of Zr4+ and Bi3+ on potassium sodium niobate ((K, Na)NbO 3 , KNN) ceramics, we revealed how Bi 0.5 A 0.5 ZrO 3 (A = K, Na, Ag, and (Na 0.82 K 0.18)) reduces the orthorhombic-tetragonal phase transition temperature (T O–T) of KNN ceramics. Investigations into the alone effects reveal that aliovalent substitutions on K+/Na+ (Nb5+) with Bi3+ (Zr4+) inevitably destroy long-range ordering (LRO) and thus worsen piezo/ferroelectric properties. Despite this, Zr4+ can replace Nb5+ within a high content, remain an orthorhombic (O) phase, and slightly increase T O–T. Although substituting on K+/Na+ with Bi3+ decreases T O–T , it already significantly destroyed LRO before shifting T O–T to room temperature. Then, investigations into the synergetic effects show that Zr4+ acts as a buffer, Bi3+ is an accelerator, and A+ is a stabilizer. The buffer can exist in KNN ceramics within a high content and neutralizes the charges caused by the accelerator that concentrates on decreasing T O–T, and the stabilizer compensates for the stability of the perovskite phase. Their synergetic effects explain why Bi 0.5 A 0.5 ZrO 3 can gradually reduce the T O–T of KNN ceramics without significantly destroying LRO. Therefore, this work helps understand how Bi 0.5 A 0.5 ZrO 3 decreases T O–T and further design the phase boundary for KNN ceramics. Image, graphical abstract [ABSTRACT FROM AUTHOR]

This work reveals the role of Bi3+ in the controlling ability of (Bi 0.5 Ag 0.5)ZrO 3 to the phase structure of potassium sodium niobate based ceramics by introducing Ba2+. The substitution on (Bi 0.5 Ag 0.5)2+ with Ba2+ results in the reduced degree of phase coexistence, accompanying the phase transition from coexisting orthorhombic-tetragonal (O–T) phases to an orthorhombic (O) phase, which is demonstrated by the systematic phase structure analysis and variations of electrical properties. The analysis reveals that the high electronegativity of Bi3+ results in the increased covalent bond character and then increases the stabilization of the T phase, leading to a decrease in orthorhombic-tetragonal phase transition temperature (T O-T). Therefore, this work not only compares the controlling ability of Ba2+ and (Bi 0.5 Ag 0.5)2+ to T O-T but also reveals which and how elements cause the decreased T O-T , promoting the understanding of the effect of additives on the phase structure. [ABSTRACT FROM AUTHOR]

The development of integration technology necessitates the miniaturization of ferroelectric devices and scaling down of materials thickness. Great value of scaling effect has presented in ferroelectric films, however, experimentally manipulated scaling effect remains ambiguous in bulk form. Here, we aim to demonstrate that the scaling effect in ferroelectric ceramics is highly sensitive to the specimen preparation, and show how it works via grinding process and site-dependent doping strategy. By taking barium titanate ceramics as an example, we find that the electro-strain of B-site substitution largely increases after halving the thickness and better strain stability with 50% increment is obtained, while A-site substitution hardly changes. The enhanced strain performance is identified as the stress-related increment of non-180° domains. This work gives insight for understanding and manipulating the scaling effect of bulk ferroelectric materials. More meaningful for normalized strain evaluation, our work demonstrates that clear indication of sample preparation should be given. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract Phase boundaries and composition design were explored to achieve both high piezoelectricity and favorable temperature stability in potassium-sodium niobate ceramics, using (1- x)(K,Na)(Nb,Sb)O 3 - x Bi(Na,K)(Zr,Sn,Hf)O 3 ceramics. A rhombohedral-tetragonal (R-T) phase boundary was constructed at x =0.035–0.04 by co-doping with Sb5+ and Bi(Na,K)(Zr,Sn,Hf)O 3. More importantly, a superior temperature stability was observed in the ceramics with x =0.035, accompanying with a stable unipolar strain at room temperature to 100 °C. The ceramics with x =0.035 also exhibited improved piezoelectric properties (e.g., piezoelectric coefficient d 33 ∼465 pC/N and electromechanical coupling factor k p =0.47) and Curie temperature (T c ∼240 °C). The Rietveld refinement and in-situ temperature-dependent piezoresponse force microscopy (PFM) results indicated that the enhancement of the piezoelectric properties was caused by the easy domain switching, high tetragonal fraction, and tetragonality, while the improved temperature stability mainly originated from the stable domain structures. [ABSTRACT FROM AUTHOR]

Abstract Background Cardiopulmonary bypass can result in lung injury. This prospective, double-blinded, randomized trial aimed to evaluate the protective effect of inhaled budesonide on lung injury after cardiopulmonary bypass. Methods Sixty patients, aged 25 to 65 years, requiring cardiopulmonary bypass were randomized to groups treated with saline or budesonide inhalation preoperatively. The respiratory mechanics were recorded. Bronchoalveolar lavage fluid was collected before cardiopulmonary bypass and after sternal closure. Serum and bronchoalveolar lavage fluid levels of proinflammatory and anti-inflammatory factors were analyzed. The primary end point was the lowest ratio of the partial pressure of arterial oxygen to the fraction of inspired oxygen after cardiopulmonary bypass. The durations of ventilation and postoperative recovery time were noted. Results Budesonide significantly improved respiratory mechanics after cardiopulmonary bypass. Budesonide improved the partial pressure of arterial oxygen to the fraction of inspired oxygen ratio from 8 to 48 hours after the operation. Budesonide shortened the durations of mechanical ventilation and postoperative recovery time. Budesonide decreased the levels of proinflammatory factors while increasing the levels of anti-inflammatory factors in bronchoalveolar lavage fluid and serum (all P <.05). The macrophage and neutrophil counts, and protein and elastase concentrations were decreased by budesonide treatment. Conclusions Budesonide treatment shortened the durations of mechanical ventilation, inhibited local and systemic inflammation, and improved respiratory function after cardiopulmonary bypass. Graphical abstract [ABSTRACT FROM AUTHOR]

In this paper, the existence of periodic solutions are obtained for a class of non-autonomous second-order p -Laplacian systems by the least action principle. [ABSTRACT FROM AUTHOR]

In this paper, the mechanical properties of a typical four-component composite solid propellants with various designed Al/oxidizer interfaces have been studied. The Al/oxidizer interfacial control is mainly realized by using the core-shell composites AP@Al and Al@RDX with different particle sizes, where Al powder was coated with a thin layer of polydopamine (PDA) as the binding sites, so that the oxidizers could crystalize on it during a rapid spray granulation process. The stress-strain curves of the above propellants at different temperatures and different tensile rates have been obtained. The dependence of the loss factor on temperature was studied by using a dynamic thermomechanical analysis (DMA). It has been shown that the fracture elongation of the interfacial modified propellants can reach 51.81% at room temperature, which is 127.3% higher than that of the blank formulation under the same formulation. Moreover, the temperature and strain rate sensitivity of interfacial controlled HTPB propellants is much less than that of traditional ones. The microstructure of these propellants at the crack sites was investigated by scanning electron microscopy (SEM) supported with micro-area in-situ tensile CT scanning technology, to clarify their damage and failure mechanisms. • Two types of core-shell Al-based composite fuels and corresponding solid propellants have been prepared. • The fracture elongation of the interfacial controlled solid propellants was improved significantly. • The temperature and strain rate sensitivity of these propellants are much less than those of traditional ones. • The fracture mode and damage evolution mechanisms of these propellants have been clarified. [ABSTRACT FROM AUTHOR]

As one of the most important lead-free piezoelectric candidates, potassium sodium niobate [(K, Na)NbO 3 , KNN] has gained popularity due to its attractive functional properties, which are much improved by chemical modifications. However, there still remains an insufficient understanding of how these dopants influence the structure and performance of KNN ceramics. Herein, we comparatively studied a series of changes triggered by introducing (Bi 0.5 Na 0.5)ZrO 3 , BaZrO 3 , and PbZrO 3 into the KNN matrix. The analysis highlights their different roles in modulating the orthorhombic-tetragonal phase transition temperature (T O-T) by considering discrepancies in the electronegativity and radius among Bi3+, Ba2+, and Pb2+ ions. The synergistic effects of the large electronegativity and the small radius of the Bi3+ ion are the key to regulating T O-T , which is relatively unaffected by Pb2+ and Ba2+ ions. Based on experimental results and first-principles calculations, a multi-scale model is proposed to summary the general law of how the electronegativity and radius of the A-site ion in AZrO 3 -type dopants synergistically affect the phase structure, ferroelectric domains, and electrical properties of KNN ceramics. Therefore, this work helps understand the role of chemical dopants in the structure and performance of KNN ceramics and promote the future composition design for high performance. [Display omitted] Proving the large off-center displacement of Bi3+ is the root cause to effectively reduce T O-T and enhance d 33 , which is absent in Pb2+ and Ba2+. [ABSTRACT FROM AUTHOR]

We report a novel method to prepare translucent and stable Ag@AgCl/g-C 3 N 4 /TiO 2 ceramic films having strong photocatalytic activities and self-cleaning capabilities under light irradiation. Colloidal silica was used as an inorganic binder and P25 TiO 2 was added as a hydrophilicity enhancer without which a smooth coating was not achievable. Ag@AgCl of particle size around 30 nm, was synthesized by in-situ oxidation of nano-silver particles in porous g-C 3 N 4 /TiO 2 films. Optimal conditions for Ag@AgCl/g-C 3 N 4 /TiO 2 preparation in terms of strongest photocatalysis were established by tests on Rhodamine B degradation under visible and full spectral irradiations. A good adhesion strength of the porous films on glass substrate was achieved. Stability and reusability of the films were assessed by cycling tests. Possible photocatalytic mechanisms are proposed based on the basis of trapping experiments. Systematic characterization of the film suggests that the in-situ oxidation is an effective and practical method to produce nanoscale Ag@AgCl. [ABSTRACT FROM AUTHOR]

Although both the phase type and fraction of multi-phase coexistence can affect the electrical properties of (K,Na)NbO 3 (KNN)-based ceramics, effects of phase fraction on their electrical properties were few concerned. In this work, through changing the calcination temperature of CaZrO 3 powders, we successfully developed the 0.96 K 0.5 Na 0.5 Nb 0.96 Sb 0.04 O 3 -0.01CaZrO 3 -0.03Bi 0.5 Na 0.5 HfO 3 ceramics containing a wide rhombohedral-tetragonal (R-T) phase coexistence with the variations of T (or R) phase fractions. It was found that higher T phase fraction can warrant a larger piezoelectric constant ( d 33 ) and d 33 also showed a linear variation with respect to tetragonality ratio ( c / a ). More importantly, a number of domain patterns were observed due to high T phase fraction and large c / a ratio, greatly benefiting the piezoelectricity. In addition, the improved ferroelectric fatigue behavior and thermal stability were also shown in the ceramics containing high T phase fraction. Therefore, this work can bring a new viewpoint into the physical mechanism of KNN-based ceramics behind R-T phase coexistence. [ABSTRACT FROM AUTHOR]

We report a facile method to prepare porous TiO 2 and ZnO photo-catalytic ceramics in which colloidal silica was added to yield nano fused silica (FS). The colloidal silica forms continuous media within the porous ceramic structure, and when calcined at 550 °C, it converted to fused silica phase which is an excellent UV wave-guiding material. With light wave guiding effect of FS and capillary effect of reaction solution in the porous channels, the photo-catalytic reactions could occur at the vast active sites at interface inside the porous bulks, as well as at the external surfaces. Photo-catalysis experiments and kinetics were investigated and analyzed. The photo-catalytic efficiencies tested for methylene blue were enhanced by a factor of 4.1 for TiO 2 /FS system and, astonishingly, by a factor of 34.6 for ZnO/FS system, when compared with pure TiO 2 and ZnO under identical testing conditions. A model of UV-waveguide ceramic systems was proposed and discussed. This study proposes a practical approach to construct UV-waveguide porous structures, of which the principle is also potentially applicable to other types of photo-catalytic materials, including visible light active photo-catalysts. [ABSTRACT FROM AUTHOR]

The mechanisms behind the high piezoelectricity of (K,Na)NbO 3 -based lead-free ceramics were investigated, including electric field-induced phase transitions and composition-driven nanodomains. The construction of a rhombohedral-tetragonal (R-T) phase boundary, confirmed using several advanced techniques, allowed a large piezoelectric constant ( d 33 ) of 450 ± 5 pC/N to be obtained in (1- x )K 0.4 Na 0.6 Nb 0.945 Sb 0.055 O 3 - x Bi 0.5 Na 0.5 (Hf 1- y Sn y )O 3 (0 ≤ x ≤ 0.06 and 0 ≤ y ≤ 0.5) ceramics possessing an ultralow Δ U T-R of 7.4 meV. More importantly, the existence of an intermediate phase, i.e., the electric-induced phase (EIP), bridging the rhombohedral R [ P s //(111)] and tetragonal T [ P s //(001)] phases during the polarization rotation was demonstrated. Striped nanodomains (∼40 nm) that easily responded to external stimulation were also observed in the ceramics with an R-T phase. Thus, the enhanced piezoelectric properties originated from EIP and the striped nanodomains. [ABSTRACT FROM AUTHOR]

Energy storage properties of {Bi 0.5 [(Na 0.8 K 0.2 ) 1- z Li z ] 0.5 } 0.96 Sr 0.04 (Ti 1- x - y Ta x Nb y )O 3 (BNKLSTTN- x / y / z ) lead-free ceramics are investigated. It is found that Ta performs better than Nb in the case of their energy storage density values, and the addition of optimum Li contents can enhance the energy storage properties by enhancing the dielectric breakdown strength (DBS). Enhanced energy storage density of 1.60 J/cm 3 under a low electric field of 90 kV/cm is achieved in BNKLSTTN-0.025/0/0.10 samples, and the fatigue-free properties are also observed. In addition, the BNKLSTTN-0.025/0/0.10 samples show the enhanced temperature dependence of energy storage density. These results indicate that the BNKLSTTN- x / y / z ceramics are one of the most promising lead-free materials for energy storage applications. [ABSTRACT FROM AUTHOR]

Lipopolysaccharide (LPS) plays an important role in lung endothelial apoptosis which is crucial for lung fibrogenesis in ARDS progression. Reactive oxygen species (ROS) has been reported to be involved in LPS-induced lung epithelial cell apoptosis. Propofol is a commonly used intravenous anesthetic agent in clinic and it could attenuate LPS-induced epithelial cells oxidation and apoptosis. However, the mechanisms are still obscure. In this study, we examined whether and how propofol attenuates LPS-induced oxidation and apoptosis in BEAS-2B cells. Compared with control group, LPS up-regulated Pin-1, phosphatase A2 (PP2A) expression, induced p66 Shc -Ser 36 phosphorylation, and facilitated p66 Shc mitochondrial translocation, thus leading to superoxide anion (O 2 − ) generation, mitochondrial cytochrome c release, active caspase 3 over-expression and cell viability inhibition. Importantly, propofol was shown to down-regulate LPS-induced PP2A expression, limit p66 Shc mitochondrial translocation, decrease O 2 − generation, inhibit mitochondrial cytochrome c release, reduce active caspase 3 expression, and recover cells viability, while propofol had no effects on LPS-induced Pin-1 expression and p66 Shc -Ser 36 phosphorylation. Moreover, the protective effects of propofol on LPS-induced BEAS-2B cells apoptosis were similar to that of calyculin A, which is an inhibitor of PP2A. We also found that FTY720, which is an activator of PP2A, can effectively reverse the protective function of propofol. Our data illustrated that propofol could alleviate LPS-induced BEAS-2B cells oxidation and apoptosis through down-regulating PP2A expression, limiting p66 Shc -Ser 36 dephosphorylation and p66 Shc mitochondrial translocation, decreasing O 2 − generation, mitochondrial cytochrome c release, activating caspase 3 expression. [ABSTRACT FROM AUTHOR]

In this study, we investigate the aluminum agglomeration characteristics in hydroxyl‑terminated polybutadiene (HTPB) and nitrate ester plasticized polyether (NEPE) propellants during combustion. Based on thermogravimetric-differential scanning calorimetry (TG-DSC), sample quenching, microscope diagnoses, and collection of condensed combustion product, the effects of oxidants and binders on the thermal decomposition and surface characteristics of quenched samples, and combustion and agglomeration characteristics of propellants were analyzed. The Al/AP/HTPB composite has a one-step exothermic process with a heat of 1723 J·g−1, which is divided into two exothermic reactions with the addition of hexogen (RDX), with the first heat release being only 102.8 J·g−1. The first heat release of NEPE propellant is 1059 J·g−1, while CL-20 reduces it to only 520.5 J·g−1. At 14 MPa, the agglomerated peak particle size of AP/HTPB propellant is the smallest (50 µm), and the agglomerated particle size of AP/RDX/HTPB is 63 µm. The aggregation peak particle size of HMX/AP/NEPE propellant is 56 µm at 14 MPa, and the aggregation peak particle size of CL-20/HMX/AP/NEPE propellant is the largest among all samples (79 µm). The agglomeration of the two propellants is all controlled by the characteristics of the melting layer on the burning surface. The existence of pockets composed by large particle ammonium perchlorate (AP) in HTPB propellant also plays an important role in the agglomeration process of aluminum particles, which is different from NEPE propellant. The decomposition of melted binder leads to the accumulation of unlighted aluminum particles, and the size of agglomerates is mainly affected by the accumulation process. The distributed heat of different kinds of oxidants during propellant combustion may lead to the rapid decomposition of the binder before aluminum ignition, leading to the aggravation of the accumulation process and the increase of the agglomerated particle size. [ABSTRACT FROM AUTHOR]