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Relaxor ferroelectrics are primary candidates for high-performance energy storage dielectric capacitors. For the practical application of capacitors, high energy storage density and high efficiency (η) are both required, the pursuit of which remains challenging. Herein, a novel 0.88Bi0.47Na0.47Ba0.06TiO3-0.12Sr(Ni1/3Nb2/3)O3 (12SNN) lead-free ceramic is proposed to enhance the energy storage properties by modulating highly dynamic polymorphic polar nanoregions (PNRs). The introduction of SNN leads to the formation of PNRs with high flexibility, regulates the ratio of rhombohedral and tetragonal PNRs, avoids polarization saturation at an electric field far below the breakdown field, and suppresses the energy loss. As a result, a high recoverable energy density (Wrec) of 7.0 J cm−3 and a high η of 81.5% are achieved simultaneously. Additionally, the superior performance is maintained across a wide range of temperatures (25–120 °C) and frequencies (1–500 Hz). Our findings indicate that the novel 12SNN ceramic shows excellent overall energy storage performance and provides a feasible method for exploring high-temperature applications in capacitors. [ABSTRACT FROM AUTHOR]

Although piezocatalysis has achieved preliminary achievements in environmental remediation and biomedical applications, large‐scale fabrication of piezocatalysts with high degradation efficiency and low cost remains challenging. In this work, a new and easy strategy to solve this challenge is innovatively proposed, that is, ceramic‐powder‐driven boosted polarization intensity, and validated the strategy is by examining potassium sodium niobate ((K, Na)NbO3, KNN) ferroelectric. KNN‐3 piezocatalyst, obtained by grinding as‐sintered ceramics into powder, shows a degradation rate (k) as high as 148 × 10−3 min−1 for rhodamine B (RhB) dye and for 31 × 10−3 min−1 for methyl orange (MO) dye, ≈18 times and 66 times than those of previously reported KNN piezocatalysts. The superior piezocatalytic activity is attributed to enhanced polarization intensity, increased oxygen vacancies, and higher charge carrier concentrations. Besides, the KNN‐3 piezocatalyst shows excellent inhibitory effects on Staphylococcus aureus and Escherichia coli strains. Therefore, the proven ceramic preparation technology enables the new strategy to mass produce high‐performance KNN piezocatalysts that hold promise for applications in dye degradation and biomedicine. [ABSTRACT FROM AUTHOR]

Objective To investigate the utilization of outpatient and inpatient services in patients with pneumoconiosis and its influencing factors. Methods By using the convenient sampling method, 199 pneumoconiosis patients were selected from the West China Fourth Hospital, and their population characteristics, medical treatment-seeking behavior, and influencing factors were investigated by using the questionnaire on pneumoconiosis patients and its influencing factors compiled by CDC of China. Multivariate logistic regression model and multivariate poisons regression model were used to analyze the influencing factors of outpatient and inpatient service utilization. Results The two-week outpatient rate of pneumoconiosis patients surveyed was 27.6%, the median number of outpatients used in one year was twice, and the annual hospitalization rate was 61.8%. For hospitalized patients, the median number of hospitalizations per year was 1, and the median cumulative hospitalization days was 30 days. The average visual health scale (VAS) score of patients was 48.3±17.4. Multivariate logistic regression and multivariate poisons regression analysis showed that pneumoconiosis patients with basic health insurance (OR = 0.067, 95% CI: 0.006-0.716), higher frequency of medication (OR=0.100, 95% CI: 0.037-0.269), and lower VAS score (OR = 0.992, 95% CI: 0.988-0.997) had less use of outpatient services. Pneumoconiosis patients with recent exacerbation of cough (OR=5.530, 95% CI: 2.446-12.501), work injury insurance (OR=1.183, 95% CI:1.015-1.379), and lower income (OR=0.980, 95% CI: 0.965-0.997) had more use of outpatient services. Pneumoconiosis patients who were married (OR=0.063, 95% CI: 0.005-0.771) and had lower VAS scores (OR=8.463, 95% CI: 3.090-23.248) had less use of inpatient services. Pneumoconiosis patients with higher frequency of medication (OR=8.463, 95% CI: 3.090-23.248), complicated with core pulmonale (OR = 1.855, 95% CI: 1.307-2.634), pneumoconiosis compensation (OR=3.358, 95% CI: 1.183-9.529), social relief (OR=1.402, 95% CI: 1.047-1.877) and more active communication with patients (OR=2.158, 95% CI: 1.061-4.390) were likely to have more use of inpatient services. Conclusion The utilization rates of outpatients and inpatients with pneumoconiosis are higher than the national average. The health status, economic level, and social support level of patients with pneumoconiosis are important factors affecting their medical treatment behavior. [ABSTRACT FROM AUTHOR]

The realization of thermally stable Tb3+-doped green emission at high temperatures in solid-state lighting is still a crucial challenge. Nevertheless, the study on modulating the thermally stable luminescence at high temperatures is seldom reported. The position of the intervalence charge transfer (IVCT) energy level is used to systematically investigate the thermal quenching performance of Tb3+-activated green-emitting phosphors with varying concentration gradients of Gd1−xTaO4:xTb3+ (x = 0.1%, 0.5%, and 2%) in this study. The IVCT energy levels were determined according to the empirical formula to show a decreasing trend, consistent with the position of the IVCT energy levels measured in the excitation and diffuse reflectance spectra. Moreover, the thermal quenching performance of different wavelength excitation positions (host absorption, 4f–5d of Tb3+, and Tb3+–Ta5+ IVCT band) is quite different. The modulation of thermal quenching performance among distinct phosphors when subjected to host excitation or IVCT excitation can be elucidated through optimal positions within the energy levels associated with IVCT. The diverse concentration gradient samples exhibit varying degrees of thermal quenching performance in the variable-temperature spectra. The fluorescence lifetimes of the samples are generally comparable but slightly lower. The quantum efficiency rapidly improves as the Tb concentration increases. The underlying mechanism governing this phenomenon is elucidated by constructing a model that encapsulates the interplay between the compensating and quenching channels, in addition to the energy conversion of Tb3+ into Gd3+. The abovementioned results indicate that the dual driving scheme of the doping concentration and excitation wavelength is an effective means to regulate the thermal quenching performance of Tb-activated green-emitting tantalate phosphors. [ABSTRACT FROM AUTHOR]

Although past studies have shown a competitive relationship between bismuth ion (Bi3+) and rare earth ions in potassium sodium niobate {(K, Na)NbO3, KNN}‐based ceramics, a comprehensive investigation of this competition has been relatively scarce. Herein, we conducted an in‐depth exploration of this competition by substituting Bi3+ with praseodymium ions (Pr3+) in KNN‐based ceramics possessing high piezoelectric properties. The substitution of Bi3+ with Pr3+ results in a decrease in the extent of multi‐phase coexistence at room temperature, an increase in domain size and grain size, and the enhancement of ferroelectricity. However, it also leads to a deterioration in piezoelectricity. Through a combination of experimental findings and first‐principles calculations, we analyzed the alterations in phase structure, ferroelectric domains, and electrical properties, attributing these changes to the competitive nature of Bi‐O and Pr‐O bonds with their distinct ionic/covalent characteristics. Consequently, this study not only unveils the underlying physical mechanism behind the competition between Bi3+ and Pr3+ ions in KNN‐based piezoceramics but also presents a novel approach to tailor the phase transition temperature, thereby facilitating the overall performance improvement of KNN‐based ceramics. [ABSTRACT FROM AUTHOR]

Background: Parkinson's disease (PD) has been regarded as a disconnection syndrome with functional and structural disturbances. However, as the anatomic determinants, the structural disconnections in PD have yet to be fully elucidated. Purpose: To non-invasively construct structural networks based on microstructural complexity and to further investigate their potential topological abnormalities in PD given the technical superiority of diffusion kurtosis imaging (DKI) to the quantification of microstructure. Material and Methods: The microstructural data of gray matter in both the PD group and the healthy control (HC) group were acquired using DKI. The structural networks were constructed at the group level by a covariation approach, followed by the calculation of topological properties based on graph theory and statistical comparisons between groups. Results: A total of 51 patients with PD and 50 HCs were enrolled. Individuals were matched between groups with respect to demographic characteristics (P >0.05). The constructed structural networks in both the PD and HC groups featured small-world properties. In comparison with the HC group, the PD group exhibited significantly altered global properties, with higher normalized characteristic path lengths, clustering coefficients, local efficiency values, and characteristic path lengths and lower global efficiency values (P <0.05). In terms of nodal centralities, extensive nodal disruptions were observed in patients with PD (P <0.05); these disruptions were mainly distributed in the sensorimotor network, default mode network, frontal-parietal network, visual network, and subcortical network. Conclusion: These findings contribute to the technical application of DKI and the elucidation of disconnection syndrome in PD. [ABSTRACT FROM AUTHOR]

Although certain efforts were paid to the effect of K/Na ratio on the phase structure and piezoelectric properties of potassium sodium niobate {(K, Na)NbO3, KNN}‐based ceramics, insufficient attention was given to the local structure and ferroelectric domains, hindering the further understanding of physical mechanisms. Herein, we studied the effect of the K/Na ratio on KNN‐based ceramics with multi‐phase coexistence from multiscale structure. High Na+ content leads to local stress heterogeneity and retains large ferroelectric domains, while high K+ content rotates the NbO6 octahedron and results in local polarity heterogeneity and distinct dielectric relaxational behavior, consequently fragmenting ferroelectric domains. The improved piezoelectricity is obtained at the equal K/Na ratio and originates from the balanced local polarity and stress heterogeneities. Therefore, an appropriate K/Na ratio should be fully considered when designing compositions with the purpose of improving performance of KNN‐based ceramics in the future. [ABSTRACT FROM AUTHOR]

Background Methods Results Conclusion The potential neuroprotective effects of dexmedetomidine against ketamine‐induced neurotoxicity remain inconclusive. This study aims to investigate the influence of dexmedetomidine on ketamine‐induced neuronal apoptosis and neurodevelopmental toxicity.In vitro experiments employed concentrations of 0.1 uM for dexmedetomidine and 50 uM for ketamine individually as well as their combination. Changes in apoptotic proteins and dendritic development in neurons were assessed after a 6‐h exposure to the drugs with evaluations conducted 24 hs' post‐treatment. In vivo experiments entailed intraperitoneal administration starting from postnatal Day 7 (P7) continuously for 3 days (P7–P9) using dosages of 100 mg/kg for ketamine and 1 mg/kg for dexmedetomidine alone or combined. Learning, memory and motor coordination abilities were evaluated via rotary rod tests and shuttle box experiments at P30 and P60, respectively.Dexmedetomidine effectively mitigated ketamine‐induced apoptosis in hippocampal neurons but did not alleviate associated dendritic developmental abnormalities. Although causing reduced motor coordination in mice, no improvement was observed with regard to this effect or reaction speed when treated with dexmedetomidine alongside ketamine.This study demonstrates that while dexmedetomidine can mitigate ketamine‐induced neuronal apoptosis, it has limited impact on its associated neurodevelopmental toxicities. [ABSTRACT FROM AUTHOR]