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The growing demand for electronic devices has induced a significant requirement for high energy density capacitors. In this investigation, we introduced small groups of cyanoethyl cellulose (CEC) into a polyimide (PI) substrate to create all organic CEC/PI composite films for high energy density capacitor applications. Due to the large dipole moment in C–CN dipoles in CEC groups, the dielectric constant of the CEC/PI-5 (5% CEC) composite increased by 26.3% to 4.31. Compared to the pristine PI film at room temperature, the breakdown field of the CEC/PI-0.5 increased by 4.7% from 502.29 to 526.1 MV m−1 and the energy storage density increased by 95% to 11.70 J cm−3. Furthermore, the CEC/PI-0.5 film exhibited an energy density of 6.39 J cm−3 with the breakdown field of 400 MV m−1 at 150 °C, which is 93.05% higher in energy densities than that of the pristine PI film. Furthermore, simulation results indicate that CEC groups can introduce deep traps in the CEC/PI composite, which can inhibit charge movement in the composite and increase the breakdown field of it. In this study, it was found that by adding small amount of CEC polar group in PI film, the high temperature energy density of CEC/PI composite materials was significantly improved. This study not only makes a significant contribution to the development of high-temperature energy-density capacitors, but also pave a way by using small molecule polar polymers to improve the energy density of dielectric materials at high temperature. [ABSTRACT FROM AUTHOR]

Recently, due to the advantages of superior compatibility, fewer interface defects, and a high electric breakdown field, all-organic dielectric composites have attracted significant research interest. In this investigation, we produced all-organic P(VDF-TrFE-CFE) terpolymer/PI (terp/PI) composite films by incorporating a small amount of terpolymer into PI substrates for high energy density capacitor applications. The resulting terp/PI-5 (5% terpolymer) composite films exhibit a permittivity of 3.81 at 1 kHz, which is 18.7% greater than that of pristine PI (3.21). Furthermore, the terp/PI-5 film exhibited the highest energy density (9.67 J/cm3) and a relatively high charge–discharge efficiency (84.7%) among the terp/PI composite films. The energy density of the terp/PI-5 film was increased by 59.8% compared to that of the pristine PI film. The TSDC results and band structure analysis revealed the presence of deeper traps in the terp/PI composites, contributing to the suppression of leakage current and improved charge–discharge efficiency. Furthermore, durability tests confirm the stability of the composite films under extended high-temperature exposure and cycling, establishing their viability for practical applications. [ABSTRACT FROM AUTHOR]

This paper uses microdata from the 2017 China Time Use Survey (CTUS) to study the impact of leisure patterns on the subjective well-being of the floating population. We find that latent profile analysis (LPA) divides the leisure time allocation patterns of the Chinese floating population into five types: self-entertainment type, family-friendly type, sports fitness type, social-entertainment type and cultural-artistic type. The empirical results show that the sports fitness type and the cultural-artistic leisure type are the most conducive to the improvement of the subjective well-being of the floating population, followed by the social-entertainment type and the family-friendly type, whereas the self-entertainment type does not contribute to the improvement of subjective well-being. The analysis of the mechanism of action shows that social integration is the mediating variable of the leisure patterns promoting the subjective well-being of the floating population. The conclusion has implications for urban managers to better help the floating population in China integrate into the new environment and improve their quality of life. [ABSTRACT FROM AUTHOR]

Real-time quantitative PCR (RT-qPCR) is widely used to measure and evaluate gene expression. The precision and reliability of RT-qPCR are critically dependent on the selection of suitable reference genes (RGs). In this study, an effort was made to identify the optimal RGs for RT-qPCR analysis of adipose and the longissimus dorsi muscle (LM) in buffaloes. RNA sequencing data were firstly analyzed to obtain 10 candidate genes (FKBP1A, C25H16orf72, PNRC2, IQGAP1, ATP5PD, RPL6, NDUFB4, TRA2A, CAPRIN1, and METAP2) that with high and stable expression across adipose tissues. Four other identified RGs (GAPDH, ACTB, TOP2B, and UXT) were selected as well. The expression stability of the candidate RGs was evaluated by three algorithms (geNorm, NormFinder, and BestKeeper) and then further validated by adipocyte and myocyte markers. Our results showed that UXT and TOP2B were the optimal RGs for RT-qPCR analysis across adipose tissues in buffaloes; three RGs, RPL6, UXT, and TOP2B, were the optimal RGs for RT-qPCR analysis across adipose and the LM tissues in buffaloes. This study provides significant information for improving the accuracy of gene expression in research on intramuscular fat deposition in buffaloes. [ABSTRACT FROM AUTHOR]

In the past few decades, ceramic/polymer nanocomposites have been extensively studied due to their relatively large dielectric constant, high electric energy density, and large charge–discharge efficiency. Antiferroelectric (AFE) materials possess a low remnant polarization (Pr) and relatively high saturation polarization (Ps), which can induce higher storage energy density than relaxor ferroelectric materials. In this investigation, AgNbO3-based AFE ceramic nanoparticles were grafted with a layer of poly(methyl methacrylate) (PMMA) to form AgNbO3–g-PMMA nanoparticles and then the obtained nanoparticles were embedded into a poly(vinylidene fluoride-hexafluoropropylene) (PVDF-HFP) matrix to form an AgNbO3–g-PMMA/PVDF-HFP (AN–g-PMMA/HFP) nanocomposite film. After characterization, it was found that the dielectric constant of the AN–g-PMMA/HFP-5 (5% AgNbO3) nanocomposite film was 12.3, which was 43% higher than that of the pristine PVDF-HFP film. The AN–g-PMMA/HFP-5 nanocomposite film exhibited the largest breakdown field of 500 MV m−1 and the highest energy density of 13 J cm−3, which was increased by 32.5% (from 9.82 to 13 J cm−3), as compared with that of the pristine PVDF-HFP film. The AN–g-PMMA/HFP-5 film exhibited a charge–discharge efficiency of 69.5% at 500 MV m−1, which is 9.5% higher than that of the pristine PVDF-HFP film. This AgNbO3-based nanocomposite film shows great promise for AFE nanocomposite for high energy density capacitor applications. [ABSTRACT FROM AUTHOR]

The critical role of IgE in allergic diseases is well-documented and clinically proven. Omalizumab, a humanized anti-IgE antibody, was the first approved antibody for the treatment of allergic diseases. Nevertheless, omalizumab still has some limitations, such as product instability and dosage restriction in clinical application. In this study, we attempted to develop an omalizumab biobetter antibody with the potential to overcome its limitations. We removed two aspartic acid isomerization hotspots in CDRs of omalizumab to improve antibody candidate's stability. Meanwhile, several murine amino acids in the framework region of omalizumab were replaced with human source to reduce the potential immunogenicity. Yeast display technology was then applied to screen antibody candidates with high binding affinity to IgE. Moreover, YTE mutation in Fc fragment was introduced into the candidates for extending their serum half-life. A lead candidate, AB1904Am15, was screened out, which showed desired biophysical properties and improved stability, high binding affinity and elevated potency in vitro , prolonged half-life in human FcRn transgenic mouse, and enhanced in vivo efficacy in cynomolgus monkey asthma model. Overall, our study developed a biobetter antibody of omalizumab, AB1904Am15, which has the potential to show improved clinical benefit in the treatment of allergic diseases. [ABSTRACT FROM AUTHOR]

Fluorescent proteins (FPs) have become fundamental tools for live cell imaging. Most FPs currently used are members of the green fluorescent protein super-family, but new fluorophores such as bilin-FPs are being developed and optimized. In particular, the UnaG FP incorporates bilirubin (BR) as a chromophore, enhancing its fluorescence quantum yield by three orders of magnitude relative to that in solution. To investigate the mechanism of this dramatic enhancement and provide a basis for further engineering of UnaG and other tetrapyrrole-based fluorophores, we performed picosecond fluorescence and femtosecond transient absorption measurements of BR bound to UnaG and its N57A site-directed mutant. The dynamics of wt-UnaG, which has a fluorescence QY of 0.51, are largely homogeneous, showing an excited state relaxation of ∼200 ps, and a 2.2 ns excited-state lifetime decay with a kinetic isotope effect (KIE) of 1.1 for D2O vs. H2O buffer. In contrast, for UnaG N57A (fluorescence QY 0.01) the results show a large spectral inhomogeneity with excited state decay timescales of 47 and 200 ps and a KIE of 1.4. The non-radiative deactivation of the excited state is limited by proton transfer. The loss of direct hydrogen bonds to the endo-vinyl dipyrrinone moiety of BR leads to high flexibility and structural heterogeneity of UnaG N57A, as seen in the X-ray crystal structure. [ABSTRACT FROM AUTHOR]