The disulfide metathesis is a promising candidate in the dynamically exchanged strategy for improving the self-healing ability of polymer electrolytes (PEs). However, the enhancement effects on the ...ionic conductivities of PEs are generally ignored while introducing a dynamic covalent bond to PEs. Herein, the oligo(ethylene oxide)-based additive containing a disulfide bond (S–S additive) was synthesized via Michael addition reaction of cystamine and poly(ethylene glycol) methyl ether acrylate (PEGA). Short PEG chains complexed with Li+ in a S–S additive migrated rapidly in PEs because of the dynamically exchanged strategy of the disulfide bond. Moreover, disulfide bonds in a S–S additive possessed the ability to exchange with the cross-linked network containing disulfide bonds (S–S net). The as-prepared PEs exhibited a high room temperature ionic conductivity of 1.24 × 10–4 S cm–1, demonstrating that the disulfide metathesis-assisted Li+ conduction was feasible for enhancing ionic conductivities of PEs. Relative to other PEO-based PEs, these disulfide-containing PEs possessed a high Li+ transference number (0.54). Furthermore, the lithium-metal batteries (LMBs) assembled with PEs in the presence of a S–S additive presented stable cycle performance, indicating the promising potential of these PEs as candidates for next-generation LMBs.
In order to explore the origin and significance of music education reform and talent cultivation in the new era, this paper constructs a new music curriculum evaluation model based on SVM. Firstly, ...we explore the path of music education reform and the goal of music talent cultivation by taking the trend of Internet of everything as the origin of the proposed “high-quality courses” for music in universities. Then, we analyzed that the recognition accuracy of SVM is significantly better than most machine learning methods in solving high-dimensional small sample data, so we established a new music curriculum teaching evaluation model on this basis. The average score of each index of the new course teaching effect is 74, and the evaluation grade is better, obtained by establishing the evaluation system of the new music course of SVM. In the evaluation index, the CVI indexes were all kept in the range of 0.82 to 0.98, which was higher than the standard 0.78 of the CVI index, and the Kappa value of each evaluation index was higher than 0.86. The attendance rate in college teaching rose from 78% to 100%, the ability to master music knowledge rose from 67% to 93%, the ability to apply knowledge rose from 76% to 92%, and the average score on weekly tests rose from 86 to 96. Finally, it is concluded that the Internet-based music education reform approach can promote the development of music education careers and cultivate the important means of all-around talents.
This study focuses on the uniaxial compressive behaviour of thin-walled Al alloy tubes filled with pyramidal lattice material. The mechanical properties of an empty tube, Al pyramidal lattice ...material, and pyramidal lattice material-filled tube were investigated. The results show that the pyramidal lattice material-filled tubes are stronger and provide greater energy absorption on account of the interaction between the pyramidal lattice material and the surrounding tube.
The metabolic syndrome (MetS) is one of the major health hazards and an epidemic worldwide. There is no known best remedy has been defined yet. In the current investigation, we designed a ...meta‐analysis of randomized clinical trials (RCTs) to evaluate the beneficial effects of tea consumption in alleviating metabolic syndromes. Herein, we accumulated the relevant literature available on PubMed and EMBASE databases from January, 2000 to August, 2019. RCTs bearing impact factor of at least 1 or more were studied for the effect of tea consumption on MetS. This meta‐analysis suggested that tea consumption has beneficial effects on diastolic blood pressure (DBP), and this finding was characterized of all types of tea in the current study and also for body mass index (BMI) value. Furthermore, this analysis also found that black tea consumption has protective effects on systolic SBP, green tea reduces the incidence of diabetes and lower the level of low‐density lipoprotein (LDL) cholesterol. These functions required BMI value at least 28 or higher. The meta data led us to conclude that tea consumption have protective effects on MetS, however, different types of tea might have different protective mechanisms on MetS, but, exact mechanisms are not yet clear and needs to be explored.
Drought limits citrus yield and fruit quality worldwide. The basic helix-loop-helix (bHLH) transcription factors (TFs) are involved in plant response to drought stress. However, few bHLH TFs related ...to drought response have been functionally characterized in citrus. In this study, a bHLH family gene, named
, was cloned from trifoliate orange. PtrbHLH66 contained a highly conserved bHLH domain and was clustered closely with bHLH66 homologs from other plant species. PtrbHLH66 was localized to the nucleus and had transcriptional activation activity. The expression of
was significantly induced by polyethylene glycol 6000 (PEG6000) and abscisic acid (ABA) treatments. Ectopic expression of
promoted the seed germination and root growth, increased the proline and ABA contents and the activities of antioxidant enzymes, but reduced the accumulation of malondialdehyde (MDA) and reactive oxygen species (ROS) under drought stress, resulting in enhanced drought tolerance of transgenic Arabidopsis. In contrast, silencing the
homolog in lemon plants showed the opposite effects. Furthermore, under drought stress, the transcript levels of 15 genes involved in ABA biosynthesis, proline biosynthesis, ROS scavenging and drought response were obviously upregulated in
ectopic-expressing Arabidopsis but downregulated in
homolog silencing lemon. Thus, our results suggested that PtrbHLH66 acted as a positive regulator of plant drought resistance by regulating root growth and ROS scavenging.
The mechanical behaviors and microstructural characteristics of three twinning-induced plasticity (TWIP) steels prepared using directional solidification at withdrawal rates of 3, 8, and 15 µms
−1
... (abbreviated as DS3, DS8, and DS15, respectively) were investigated. The results showed that all the samples solidified steadily in a cellular growth mode. The dendrite spacing decreased on increasing the withdrawal rate, but eliminated grains resulted from increased growth competition. At a low strain rate of 2.27×10
−3
s
−1
, DS8 exhibited the best mechanical properties because of the adequately stimulated TWIP effect with well-developed twin structures and good deformation synergy between columnar grains being conducive to uniform stress distribution. Therefore, the work hardening ability significantly improved, with the highest working hardening exponent,
n
i
, obtained at a high strain level. This was accompanied by a remarkably enhanced uniform plastic deformation ability. A weakened TWIP effect occurred due to suppressed twinning with fewer and nonuniform twins structures at a high strain rate of 3.79×10
-1
s
-1
. The high strain rate was evident to be not conducive to the activation of planar slip for directionally solidified samples, resulting in fewer and inhomogeneous slip systems. This effectively weakened twinning with relatively strong dislocation gliding instead. This remarkably decreased all the
n
i
values in the medium-to-high strain range, leading to a significantly decreased plastic deformation ability and finally resulting in severely degraded plasticity, especially for DS8.
Acute lung injury (ALI) is an inflammatory disorder of the lung that causes high mortality and lacks any pharmacological intervention. Ubiquitination plays a critical role in the pathogenesis of ALI ...as it regulates the alveolocapillary barrier and the inflammatory response. Tripartite motif (TRIM) proteins are one of the subfamilies of the RING-type E3 ubiquitin ligases, which contains more than 80 distinct members in humans involved in a broad range of biological processes including antivirus innate immunity, development, and tumorigenesis. Recently, some studies have shown that several members of TRIM family proteins play important regulatory roles in inflammation and ALI. Herein, we integrate emerging evidence regarding the roles of TRIMs in ALI. Articles were selected from the searches of PubMed database that had the terms “acute lung injury,” “ubiquitin ligases,” “tripartite motif protein,” “inflammation,” and “ubiquitination” using both MeSH terms and keywords. Better understanding of these mechanisms may ultimately lead to novel therapeutic approaches by targeting TRIMs for ALI treatment.
Chemical fuel-driven supramolecular systems have been developed showing out-of-equilibrium functions such as transient gelation and oscillations. However, these systems suffer from undesired waste ...accumulation and they function only in open systems. Herein, we report non-equilibrium supramolecular polymerizations in a closed system, which is built by viologens and pyranine in the presence of hydrazine hydrate. On shaking, the viologens are quickly oxidated by air followed by self-assembly of pyranine into micrometer-sized nanotubes. The self-assembled nanotubes disassemble spontaneously over time by the reduced agent, with nitrogen as the only waste product. Our mechanosensitive dissipative system can be extended to fabricate a chiral transient supramolecular helix by introducing chiral-charged small molecules. Moreover, we show that shaking induces transient fluorescence enhancement or quenching depending on substitution of viologens. Ultrasound is introduced as a specific shaking way to generate template-free reproducible patterns. Additionally, the shake-driven transient polymerization of amphiphilic naphthalenetetracarboxylic diimide serves as further evidence of the versatility of our mechanosensitive non-equilibrium system.
Auxetic materials are a class of materials that expand transversely when stretched longitudinally. Recently, auxetic materials are gaining special interest in wide range of applications mainly due to ...their attractive mechanical behavior. In this study, we focus on the compressive properties of new three-component auxetic composite-filled tubes including empty tubes, auxetic lattice structures and polymer fillers. The compressive behavior of three-component auxetic composite-filled tubes, auxetic composites and empty tube was investigated by means of finite element analysis (FEA) and experimental method. The results indicated that the auxetic composite-filled tubes exhibit superior behavior compared with both the empty tube and auxetic composites, even significantly higher stress than the sum of total thereof. This feature is related to the interaction effect and additional support between the three components. The energy absorption characteristics and deformation modes of the auxetic composite-filled tubes and empty tube were also ascertained. It was concluded that inserting auxetic composite as a filler material inside the empty tube significantly improved its energy absorption, as well as delaying crack initiation and propagation in the empty tube.
Understanding the correlation of plasticity with deformation and dynamic recrystallization (DRX) behaviors, in magnesium (Mg) alloys deformed under high-strain-rate conditions, is increasingly ...important for wrought Mg processing. In the present study, a ZK30 (Mg-2.61%Zn-0.66%Zr by weight percent (wt.%)) alloy in the as-forged state was hot compressed to various strain levels at a temperature of 350 °C and a strain rate of 10 s
. Heterogeneous deformation and dynamic recrystallization (DRX) behaviors of the complicated microstructures in the deformed samples were analyzed via a grain-partitioning approach based on intra-grain misorientation analysis from electron back-scattered diffraction (EBSD). The ZK30 alloy showed excellent formability, remaining intact at a true strain of -1.11. Continuous dynamic recrystallization (CDRX) and discontinuous dynamic recrystallization (DDRX) via grain boundary corrugation/bulging are the dominant mechanisms for the relaxation of strain energy during hot compression. Initial Zr-rich coarse grains undertook a significant portion of the plastic strain as the compression progressed, reflected by the increased misorientations within their interior and marked change in their aspect ratios. The results indicate that the excellent plasticity of the as-forged ZK30 alloy can be attributed to the operative CDRX mechanisms and the reduced deformation anisotropy of Zr-rich coarse grains containing Zn-Zr nano-precipitates.
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