Enhanced Absolute Recovered Energy under Low Electric Field in All-Inorganic 0-3 Nanocomposition Thick Films.

Inorganic thick-film dielectric capacitors with ultrahigh absolute recovered energy at low electric fields are extremely desired for their wide application in pulsed power systems. However, a long-standing technological bottleneck exists between high absolute energy and large recovered energy density. A new strategy is offered to fabricate selected all-inorganic 0-3 composite thick films up to 10 µm by a modified sol-slurry method. Here, the ceramic powder is dispersed into the sol-gel matrix to form a uniform suspension, assisted by powder, therefore, the 2 µm-thickness after single layer spin coating. To enhance the energy-storage performances, the composites process is thoroughly optimized by ultrafine powder (<50 nm) technique based on a low-cost coprecipitation method instead of the solid-state and sol-gel methods. 0D coprecipitation powder has a similar dielectric constant to the corresponding 3D films, thus uneven electrical field distributions is overcome. Moreover, the increase of interfacial polarization is realized due to the larger specific surface area. A maximum recoverable energy density of 14.62 J cm-3 is obtained in coprecipitation thick films ≈2.2 times that of the solid-state powder and ≈1.3 times for sol-gel powder. This study provides a new paradigm for further guiding the design of composite materials.

Enhancement of Ultrasonic Transducer Bandwidth by Acoustic Impedance Gradient Matching Layer.

High-performance broadband ultrasound transducers provide superior imaging quality in biomedical ultrasound imaging. However, a matching design that perfectly transmits the acoustic energy between the active piezoelectric element and the target medium over the operating spectrum is still lacking. In this work, an anisotropic gradient acoustic impedance composite material as the matching layer of an ultrasonic transducer was designed and fabricated; it is a non-uniform material with the continuous decline of acoustic impedance along the direction of ultrasonic propagation in a sub-wavelength range. This material provides a broadband window for ultrasonic propagation in a wide frequency range and achieves almost perfect sound energy transfer efficiency from the piezoelectric material to the target medium. Nano tungsten particles and epoxy resin were selected as filling and basic materials, respectively. Along the direction of ultrasonic propagation, the proportion of tungsten powder was carefully controlled to decrease gradually, following the natural exponential form in a very narrow thickness range. Using this new material as a matching layer with high-performance single crystals, the -6 dB bandwidth of the PMN-PT ultrasonic transducer could reach over 170%, and the insertion loss was only -20.3 dB. The transducer achieved a temporal signal close to a single wavelength, thus there is the potential to dramatically improve the resolution and imaging quality of the biomedical ultrasound imaging system.

In vivo assembly enhanced binding effect augments tumor specific ferroptosis therapy.

Emerging evidence indicates that the activation of ferroptosis by glutathione peroxidase 4 (GPX4) inhibitors may be a prominent therapeutic strategy for tumor suppression. However, the wide application of GPX4 inhibitors in tumor therapy is hampered due to poor tumor delivery efficacy and the nonspecific activation of ferroptosis. Taking advantage of in vivo self-assembly, we develop a peptide-ferriporphyrin conjugate with tumor microenvironment specific activation to improve tumor penetration, endocytosis and GPX4 inhibition, ultimately enhancing its anticancer activity via ferroptosis. Briefly, a GPX4 inhibitory peptide is conjugated with an assembled peptide linker decorated with a pH-sensitive moiety and ferriporphyrin to produce the peptide-ferriporphyrin conjugate (Gi-F-CAA). Under the acidic microenvironment of the tumor, the Gi-F-CAA self-assembles into large nanoparticles (Gi-F) due to enhanced hydrophobic interaction after hydrolysis of CAA, improving tumor endocytosis efficiency. Importantly, Gi-F exhibits substantial inhibition of GPX4 activity by assembly enhanced binding (AEB) effect, augmenting the oxidative stress of ferriporphyrin-based Fenton reaction, ultimately enabling antitumor properties in multiple tumor models. Our findings suggest that this peptide-ferriporphyrin conjugate design with AEB effect can improve the therapeutic effect via induction of ferroptosis, providing an alternative strategy for overcoming chemoresistance.

Single-cell analyses EMP1 as a marker of the ratio of M1/M2 macrophages is associated with EMT, immune infiltration, and prognosis in bladder cancer.

Background: Bladder cancer is among the most lethal urinary system cancers across the globe. Macrophage 1 and Macrophage 2 play an essential role in the pathogenesis of tumors. Nevertheless, prior studies failed to investigate the implication of the two cells, working in combination, in the development, growth, progression and metastasis of bladder cancer. Methods: We computed the M1/M2 ratio of the samples retrieved from The Cancer Genome Atlas (TCGA) by using the Cibersortx algorithm and calculated the ratio in 32 patients in our series by employing flow cytometry. SurvivalRandomForest was utilized to reduce the dimension of the list of the M1/M2-related genes, with an aim to obtain the most survival-predictive gene (EMP1) encoding epithelial membrane protein 1 (EMP1). The EMP1 was biologically characterized by using Gene Set Enrichment Analysis (GSEA), Gene Set Variation Analysis (GSVA), and Gene Ontology (GO). The single-cell transcriptome (sc-RNA) analysis was then applied to further look into the function of EMP1. Finally, Cellchat was employed to examine the interaction between macrophages and epithelium cells. Results: The results showed that higher M1/M2 ratio was found to be associated with a more favorable prognosis of bladder cancer. EMP1 was identified to be the key gene indicative of M1/M2 ratio and higher EMP1 expression was associated with poor prognosis. Further analyses showed that EMP1 might promote tumor invasion and metastasis via epithelial-mesenchymal transition (EMT) and focal adhesion (FA). Moreover, the expression level of EMP1 could serve as an indicator of immunotherapy efficacy. The scRNA-seq data indicated that EMP1 in cancer cells was strongly associated with tumor proliferation. Finally, the Cellchat results exhibited that EMP1 might promote the interaction between macrophages and cancer cells through the fibronectin 1-syndecan 1 (FN1-SDC1) pathway. Conclusion: Our study identified EMP1, an M1/M2-related gene, the expression of which may act as a prognostic indicator for the proliferation, metastasis, and response to immunotherapy. EMP1 might be involved in the regulation on M1/M2 ratio.

[Risk Assessment and Sources of Heavy Metals in Farmland Soils of Yellow River Irrigation Area of Ningxia].

The farmland environment is directly related to the quality and safety of agricultural products. In order to understand the characteristics and main influencing factors of heavy metals in farmland soil in the Yellow River irrigation area of Ningxia, sampling and monitoring were conducted for five consecutive years from 2017 to 2021, and the distribution characteristics and correlation of heavy metals were analyzed. The pollution status and potential ecological risks of heavy metals were evaluated, and the main sources of heavy metals in farmland were analyzed. The results showed that the average values of Pb, As, Zn, Ni, Cu, Hg, Cr, and Cd in the soil of the Ningxia Yellow River irrigation area were 19.74, 11.67, 66.88, 29.09, 22.55, 0.03, 62.27, and 0.19 mg·kg-1, respectively, which were enriched to some extent compared with the background values of the soil environment in Ningxia. Among them, Hg and Cd had middle- and high-grade ecological risk points; however, none of them exceeded the control value of agricultural land soil pollution risk, and all sampling sites had no high-risk or extremely high-risk levels. The results of source analysis based on positive matrix factorization (PMF) and correlation analysis showed that there were five main sources of heavy metals in farmland soil in the study area: natural sources, mixed sources of industrial and mining activities and the production and life of residents, transportation sources, agricultural production activities sources, and industrial sources, with contribution rates of 26.54%, 25.59%, 22.52%, 15.63%, and 9.72%, respectively. On the whole, the heavy metals in farmland soil in the Ningxia Yellow River irrigation area did not exceed the standard, and there was no high-level ecological risk. The production environment of the farmland soil was good, but the contribution rate of human activities to soil heavy metals was large.

Pyroptosis-Related Subtypes Predict the Response of Clear Cell Renal Cell Carcinoma to Targeted Therapy.

BACKGROUND: Pyroptosis plays a crucial role in anti-tumor immunity and in formation of the immune microenvironment. However, whether pyroptosis is involved in the progression of clear cell renal cell carcinoma (ccRCC) is still unclear. Personalized treatment of ccRCC requires detailed molecular classification to inform a specific therapy. METHODS: Molecular subtyping of ccRCC was performed based on consensus clustering of pyroptosis-related genes. The characteristics of these molecular subtypes were explored at the genome, transcriptome and protein levels. Single-cell RNA sequencing and CIBERSORT analysis were used to analyse the immune microenvironment of ccRCC, while Lasso regression was used to develop a prediction model based on hub genes. Expression of the pyroptosis-related gene GSDMB was also investigated at the tissue and cellular levels. RESULTS: Two molecular subtypes were identified based on the clustering of pyroptosis-related genes. Cluster 1 was associated with activation of classical oncogenic pathways, especially the angiogenesis pathway. Cluster 2 was associated with activation of immune-related pathways and high levels of immunosuppressive cells, exhausted CD8+ T cells, and tumor-associated fibroblast infiltration. Clusters 1 and 2 were thus defined as the angiogenic and inflamed subtypes, respectively. The two subtypes were predictive of the response of ccRCC to anti-angiogenic therapy and immunotherapy, with Cluster 1 patients benefiting from anti-angiogenic therapy and Cluster 2 patients showing better response to anti-PD1 inhibitor therapy. Furthermore, a 9-gene expression signature (HJURP, NUF2, KIF15, MELK, TPX2, PLK1, CDCA3, CTLA4, FOXP3) was identified that could predict outcome and response to immune checkpoint blockade therapy in test cohorts. Finally, GSDMB was found to be involved in the development of renal clear cell carcinoma. CONCLUSIONS: These results on pyroptosis-related genes in ccRCC provide a theoretical basis for understanding molecular heterogeneity and for the development of individualized treatment strategies.

Increasing Performances of 1-3 Piezocomposite Ultrasonic Transducer by Alternating Current Poling Method.

Ultrasonic transducers are the basic core component of diagnostic imaging devices, wherein the piezoelectric materials are the active element of transducers. Recent studies showed that the alternating current poling (ACP) method could develop the properties of piezocomposites, which had great potential to improve transducer performance. Herein, transducers (fc = 3 MHz) made of DCP and ACP 1-3 piezocomposites (prepared by PZT-5H ceramics and PMN-PT single crystals) were fabricated. The effect of the ACP method on the bandwidth and insertion loss (sensitivity) was explored. The results indicate that the ACP method can significantly enhance the bandwidth and slightly increase the insertion loss of transducers. Particularly, a superhigh bandwidth of 142.8% was achieved in the transducer of ACP 1-3 PMN-PT single crystal combined with suitable matching and backing layers. This bandwidth is higher than that of all reported transducers with similar center frequency. Moreover, the optimization mechanism of transducer performance by the ACP method was discussed. The obtained results suggested that the ACP is an effective and convenient technology to improve transducer performances, especially for the bandwidth.

Transformable ECM Deprivation System Effectively Suppresses Renal Cell Carcinoma by Reversing Anoikis Resistance and Increasing Chemotherapy Sensitivity.

Extracellular matrix (ECM) is crucial in various biological functions during tumor progression, including induction of anoikis resistance and cell adhesion-mediated drug resistance (CAM-DR). Fibronectin (FN) is a vital ECM component with direct regulatory effects on ECM-mediated anoikis resistance and CAM-DR, making it an attractive and innovative therapeutic target for depriving ECM in tumor tissue. Herein, an ECM deprivation system (EDS) is developed based on FN targeting self-assembly peptide for constructing nanofibers in the ECM of renal cell carcinoma (RCC), which contributes to: i) targeting and recognizing FN to form nanofibers for long-term retention in ECM, ii) reversing anoikis resistance via arresting the FN signaling pathway, and iii) serving as a drug-loading platform for sensitizing chemotherapy by ameliorating CAM-DR. The results reveal that EDS significantly reverses anoikis resistance of RCC cells by inhibiting the phosphorylation of FAK, a positive regulator of the FN signaling pathway. Meanwhile, EDS serves as a chemotherapy-sensitizer of cancer, exerting significant synergistic effects with doxorubicin (DOX). In vivo validation experiments show that EDS effectively suppresses metastasis and tumor growth with chemotherapy resistance. Collectively, the innovative EDS notably inhibits the tumor-promoting effect of ECM and may provide a novel approach for suppressing ECM and enhancing chemo-drug sensitivity.

[Soil enzyme activities and their stoichiometry at different altitudes in Helan Mountains, Northwest China]. / è´ºå °å±±ä¸åŒæµ·æ‹”åœŸå£¤é ¶æ´»æ€§åŠå ¶åŒ–å­¦è®¡é‡ç‰¹å¾.

Understanding altitudinal variation characteristics and driving mechanism of soil enzyme activities and their stoichiometry is of great significance for studying nutrient cycling in fragile mountain forest ecosystems. In this study, we collected soil samples from different altitudes (1380-2438 m) in Helan Mountains to analyze the altitudinal changes in soil physicochemical properties, soil enzyme activities and their stoichiometry and its influencing factors. The results showed that the activities of ß-glucosidase (ßG) and ß-N-acetylglucosaminidase (NAG) and the enzyme activities ratios of soil C/N and soil C/P firstly increased and then decreased with increasing altitude, which all peaked at 2139 m. Alkaline phosphatase (AKP) activities increased with the increases of altitude, with the maximum being found at 2438 m. However, L-leucine aminopeptidase (LAP) activities and soil N/P enzyme activities ratios did not change with increasing altitude. Compared with the soil enzyme stoichiometry in other regions of the world, Helan Mountains showed a certain degree of N limitation. Except for LAP, the activities of the other three enzymes were significantly positively correlated with the ratios of soil organic carbon/total nitrogen, soil organic carbon/total phosphorus, and total nitrogen/total phosphorus, and negatively correlated with pH. The LAP, soil C/P enzyme activities ratios and soil N/P enzyme activities ratios showed significant negative correlation with TP. In addition, AKP was significantly negatively correlated with soil bulk density.

Ionic liquid-based salt-induced liquid-liquid extraction of polyphenols and anthraquinones in Polygonum cuspidatum.

Ionic liquid-based salt-induced liquid-liquid extraction was developed for the first time and applied to the extraction of four active constituents, including polydatin, resveratrol, emodin, and physcion in Polygonum cuspidatum (P. cuspidatum). In this study, ionic liquid was used as extraction solvent. The dried P. cuspidatum samples purchased from the pharmacy were triturated and passed through a 120-mesh sieve. The obtained sample powders were dried to constant weight at 55 ℃, and then mixed with extraction solvent. The extraction was carried out with the aid of ultrasound. Three phases, including ionic liquid-rich, salt-rich and solid sample phases were formed in the presence of salt. The target analytes were enriched in ionic liquid phase and then determined by high performance liquid chromatography. The experimental parameters, such as type and volume of ionic liquid, type and amount of salt, pH value of extraction medium, ultrasound power, ultrasound time and centrifugal condition, were optimized. The calibration curves showed good linear relationship (r > 0.9994). The limits of detection and quantification were in the range of 2.8-29.5 and 9.4-98.3 ng mL-1, respectively. The spiked recoveries were between 92.16% and 105.41%. Compared with hot reflux extraction and ultrasound-assisted extraction, the proposed method requires less extraction solvent and time. The present method can be applied to the determination of polyphenols and anthraquinones in P. cuspidatum.

Equal-area criterion in power systems revisited.

The classic equal-area criterion (EAC) is of key importance in power system analysis, and provides a powerful, pictorial and quantitative means of analysing transient stability (i.e. the system's ability to maintain stable operation when subjected to a large disturbance). Based on the traditional EAC, it is common sense in engineering that there is a critical cleaning time (CCT); namely, a power system is stable (unstable) if a fault is cleared before (after) this CCT. We regard this form of CCT as bipartite. In this paper, we revisit the EAC theory and, surprisingly, find different kinds of transient stability behaviour. Based on these analyses, we discover that the bipartite CCT is only one type among four major types, and, actually, the forms of CCT can be diversified. In particular, under some circumstances, a system may have no CCT or show a periodic CCT. Our theoretical analysis is verified by numerical simulations in a single-machine-infinite-bus system and also in multi-machine systems. Thus, our study provides a panoramic framework for diverse transient stability behaviour in power systems and also may have a significant impact on applications of multi-stability in various other systems, such as neuroscience, climatology or photonics.

Linking Empowering Leadership and Employee Work Engagement: The Effects of Person-Job Fit, Person-Group Fit, and Proactive Personality.

Based on person-environment fit theory, this study examined the effects of empowering leadership on employee work engagement. We also investigated the mediating mechanism of person-job fit and person-group fit. In addition, we explored employee proactive personality's moderating role between empowering leadership and the above two kinds of fit, and then the set of indirect effects. Using a survey sample of 6179 employees from a technology company in China, we found that empowering leadership has a positively indirect influence on employees work engagement though person-job fit and person-group fit. Further, moderated mediation analysis revealed proactive personality augmented empowering leadership direct effect on person-job fit and person-group fit and indirect effect on work engagement. Theoretical and practical implications were also discussed.

Dynamics and Collapse in a Power System Model with Voltage Variation: The Damping Effect.

Complex nonlinear phenomena are investigated in a basic power system model of the single-machine-infinite-bus (SMIB) with a synchronous generator modeled by a classical third-order differential equation including both angle dynamics and voltage dynamics, the so-called flux decay equation. In contrast, for the second-order differential equation considering the angle dynamics only, it is the classical swing equation. Similarities and differences of the dynamics generated between the third-order model and the second-order one are studied. We mainly find that, for positive damping, these two models show quite similar behavior, namely, stable fixed point, stable limit cycle, and their coexistence for different parameters. However, for negative damping, the second-order system can only collapse, whereas for the third-order model, more complicated behavior may happen, such as stable fixed point, limit cycle, quasi-periodicity, and chaos. Interesting partial collapse phenomena for angle instability only and not for voltage instability are also found here, including collapse from quasi-periodicity and from chaos etc. These findings not only provide a basic physical picture for power system dynamics in the third-order model incorporating voltage dynamics, but also enable us a deeper understanding of the complex dynamical behavior and even leading to a design of oscillation damping in electric power systems.