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Dielectric elastomer actuators (DEAs) with large electrically-actuated strain can build light-weight and flexible non-magnetic motors. However, dielectric elastomers commonly used in the field of soft actuation suffer from high stiffness, low strength, and high driving field, severely limiting the DEA’s actuating performance. Here we design a new polyacrylate dielectric elastomer with optimized crosslinking network by rationally employing the difunctional macromolecular crosslinking agent. The proposed elastomer simultaneously possesses desirable modulus (~0.073 MPa), high toughness (elongation ~2400%), low mechanical loss (tan δ m  = 0.21@1 Hz, 20 °C), and satisfactory dielectric properties ( ε r  = 5.75, tan δ e  = 0.0019 @1 kHz), and accordingly, large actuation strain (118% @ 70 MV m −1 ), high energy density (0.24 MJ m −3 @ 70 MV m −1 ), and rapid response (bandwidth above 100 Hz). Compared with VHB TM 4910, the non-magnetic motor made of our elastomer presents 15 times higher rotation speed. These findings offer a strategy to fabricate high-performance dielectric elastomers for soft actuators. Dielectric elastomer actuators (DEAs) with large electrically actuated strain can be used in non-magnetic motors, but high stiffness, poor strength and slow response currently limit the application of DEAs. Here, the authors optimize the crosslinking network in a polyacrylate elastomer to enable a DEA with high toughness and actuation strain and use the polyacrylate to build a motor which can be driven under low electric field.

Dielectric elastomers, used as driver modules, require high power density to enable fast movement and efficient work of soft robots. Polyacrylate elastomers usually suffer from low power density under low electric fields due to limited response frequency. Here, we propose a bimodal network polyacrylate dielectric elastomer which breaks the intrinsic coupling relationship between dielectric and mechanical properties, featuring relatively high dielectric constant, low Young’s modulus, and wide driving frequency bandwidth (~200 Hz) like silicones. Therefore, an ultrahigh power density (154 W kg −1 @20 MV m −1 , 200 Hz) is realized at low electric field and high resonance frequency, 75 times greater than at 10 Hz. Further, a rotary motor is developed, reaching an impressive speed of 1245 rpm at 19.6 MV m −1 and 125 Hz, surpassing previous acrylate-based motors and entering the high-speed domain of silicone-based motors. These findings offer a versatile strategy to fabricate high-power-density dielectric elastomers for low-electric-field soft actuators. The authors make a bimodal network polyacrylate dielectric elastomer featuring high driving frequency like silicones and thereby a high power density of 154 W kg −1 @20 MV m −1 , 200 Hz. Their rotary motor realizes a maximum rotating speed of 1245 rpm@ 19.6 MV m −1 .

Electroactive polymer (EAP) is a kind of smart material, which can change its shape under the stimulation of electric field. Dielectric elastomer (DE) is an important member of the EAP. DE has the characteristics of excellent performance, such as light weight, low noise, low cost, and so on, which guarantee its wide applications in the fields of actuators, generators, sensors. In this review, the principles of energy conversion, the research status and latest development of new technologies for DEs, and the performance characteristics of DEs are summarised. Simultaneously, it points out the development problems and feasible countermeasures. At last, the application prospects of DE are discussed, combined with the research direction of the international frontier.

Background Ethylene-responsive factors (ERFs) play important roles in plant growth and development and the response to adverse environmental factors, including abiotic and biotic stresses. Results In the present study, we identified 160 soybean ERF genes distributed across 20 chromosomes that could be clustered into eight groups based on phylogenetic relationships. A highly ABA-responsive ERF gene, GmERF75 , belonging to Group VII was further characterized. Subcellular localization analysis showed that the GmERF75 protein is localized in the nucleus, and qRT-PCR results showed that GmERF75 is responsive to multiple abiotic stresses and exogenous hormones. GmERF75 -overexpressing Arabidopsis lines showed higher chlorophyll content compared to WT and mutants under osmotic stress. Two independent Arabidopsis mutations of AtERF71 , a gene homologous to GmERF75 , displayed shorter hypocotyls, and overexpression of GmERF75 in these mutants could rescue the short hypocotyl phenotypes. Overexpressing GmERF75 in soybean hairy roots improved root growth under exogenous ABA and salt stress. Conclusions These results suggested that GmERF75 is an important plant transcription factor that plays a critical role in enhancing osmotic tolerance in both Arabidopsis and soybean.

Large deformability and high sensitivity is difficult to be realized simultaneously in flexible sensors. Herein, taking advantage of the high permittivity and highly active surfaces of the ultrasmall barium titanate nanoparticles (BT NPs) and the high stretchability of the p(BA‐GMA) elastomer matrix, we propose a high‐performance soft stretchable sensor. The addition of the ultrasmall BT NPs can not only increase the permittivity and capacitance of polyacrylate‐matrix composite dielectric material to obtain a high sensitivity, but also basically maintains the excellent mechanical properties of the polymer matrix. The dielectric constants of the composite films increase from 5.68 to 13.13 at 10 kHz with the increase of BT NPs content from 0 to 15 vol.%, which results in a high capacitance of 236.16 pF for 15 vol.% BT/p(BA‐GMA) sensor. Combining the high permittivity and the large deformability (a maximal deformation of 87.2%), the 15 vol.% BT/p(BA‐GMA) sensor has high sensitivity and shows high linearity and stable output even if under dynamic measurement. The dual‐mode sensor that utilizes the orthogonality of capacitance‐resistance is designed, which shows excellent performance in monitoring human body movements and noncontact measurement. The results present that the BT/p(BA‐GMA)‐based sensor has high stability and reliability not exceed 65°C, which can meet the application requirements in dynamic monitoring. Ultrasmall barium titanate nanoparticles are added to the p(BA‐GMA) matrix to prepare a flexible sensor. The dielectric constants of the composite films is improved，which results in a high capacitance of 236.16 pF and a high sensitivity. The sensor shows excellent performance in monitoring human body movements.

Oxidative stress caused by accumulation of reactive oxygen species (ROS) is capable of damaging effects on numerous cellular components. Glutathione peroxidases (GPXs, EC 1.11.1.9) are key enzymes of the antioxidant network in plants. In this study, W69 and W106, two putative GPX genes, were obtained by de novo transcriptome sequencing of salt-treated wheat (Triticum aestivum) seedlings. The purified His-tag fusion proteins of W69 and W106 reduced H2O2 and t-butyl hydroperoxide (t-BHP) using glutathione (GSH) or thioredoxin (Trx) as an electron donor in vitro, showing their peroxidase activity toward H2O2 and toxic organic hydroperoxide. GFP fluorescence assays revealed that W69 and W106 are localized in chloroplasts. Quantitative real-time PCR (Q-RT-PCR) analysis showed that two GPXs were differentially responsive to salt, drought, H2O2, or ABA. Isolation of the W69 and W106 promoters revealed some cis-acting elements responding to abiotic stresses. Overexpression of W69 and W106 conferred strong tolerance to salt, H2O2, and ABA treatment in Arabidopsis. Moreover, the expression levels of key regulator genes (SOS1, RbohD and ABI1/ABI2) involved in salt, H2O2 and ABA signaling were altered in the transgenic plants. These findings suggest that W69 and W106 not only act as scavengers of H2O2 in controlling abiotic stress responses, but also play important roles in salt and ABA signaling.

Abscisic acid (ABA) mediates various abiotic stress responses, and ethylene responsive factors (ERFs) play vital role in resisting stresses, but the interaction of these molecular mechanisms remains elusive. In this study, we identified an ABA-induced soybean ERF gene that was highly up-regulated by ethylene (ET), drought, salt, and low temperature treatments. Subcellular localization assay showed that the GmERF135 protein was targeted to the nucleus. Promoter -acting elements analysis suggested that numerous potential stress responsive -elements were distributed in the promoter region of , including ABA-, light-, ET-, gibberellin (GA)-, and methyl jasmonate (MeJA)-responsive elements. Overexpression of in enhanced tolerance to drought and salt conditions. In addition, promoted the growth of transgenic hairy roots under salt and exogenous ABA conditions. These results suggest that soybean GmERF135 may participate in both ABA and ET signaling pathways to regulate the responses to multiple stresses.

Abnormal activation of PI3K/AKT/mTOR (PAM) pathway, caused by PIK3CA mutation, KRAS mutation, PTEN loss, or AKT1 mutation, is one of the most frequent signaling abnormalities in breast carcinoma. However, distribution and frequencies of mutations in PAM pathway are unclear in breast cancer patients from the mainland of China and the correlation between these mutations and breast cancer outcome remains to be identified. A total of 288 patients with invasive ductal breast cancer were recruited in this study. Mutations in PIK3CA (exons 4, 9 and 20), KRAS (exon 2) and AKT1 (exon 3) were detected using Sanger sequencing. PTEN loss was measured by immunohistochemistry assay. Correlations between these genetic aberrations and clinicopathological features were analyzed. The frequencies of PIK3CA mutation, KRAS mutation, AKT1 mutation and PTEN loss were 15.6%, 1.8%, 4.4% and 35.3%, respectively. However, except for PTEN loss, which was tied to estrogen receptor (ER) status, these alterations were not associated with other clinicopathological features. Survival analysis demonstrated that PIK3CA mutation, PTEN loss and PAM pathway activation were not associated with disease-free survival (DFS). Subgroup analysis of patients with ER positive tumors revealed that PIK3CA mutation more strongly reduced DFS compared to wild-type PIK3CA (76.2% vs. 54.2%; P = 0.011). PIK3CA mutation was also an independent factor for bad prognosis in ER positive patients. AKT1, KRAS and PIK3CA mutations and PTEN loss all exist in women with breast cancer in the mainland China. PIK3CA mutation may contribute to the poor outcome of ER positive breast carcinomas, providing evidence for the combination of PI3K/AKT/mTOR inhibitors and endocrine therapy.

Lysimachia yulongensis Z.K.Wu & Ming Y.Sheng, a new species of Primulaceae from Yunnan, China, is described and illustrated. Morphological evidence places L. yulongensis within Lysimachia sect. Pumilae , which is distinguished by dwarf plants with prostrate or nearly erect habits, few flowers clustered at the stem apex or solitary in the leaf axils near the apex, lanceolate sepals, elliptical and dorsifixed anthers and styles approximately as long as the stamens. The new species is characterised by a strongly stoloniferous growth habit, with creeping stems serving a vegetative function as stolon and terminating in leaf rosettes during fruiting; leaves that are narrowly elliptic to oblanceolate or spatulate; and flowers solitary in the leaf axils along obliquely ascending stems. Information on the distribution, phenology and conservation status of the new species is also provided.

Most commonly used dielectric elastomers (DEs) such as acrylic dielectric elastomers VHBTM 4910 need a high actuation voltage and pre‐stretching to obtain a large actuation strain, and present high mechanical loss caused by viscoelasticity. In this work, we fabricated a new acrylic elastomer by UV curing based on CN9021 and lauryl acrylate. By manipulating crosslinker content, crosslink density changed and physical entanglements of the new material can be affected. Therefore, mechanical properties such as Young's Modulus and mechanical loss of the new material can be controlled, and little change of its glass transition temperature was induced. Results of the actuation test show that the new DE is capable of 9.0% actuation area strain under 11 kV/mm and a good performance under oscillating voltage with different waveforms and frequencies.