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Dielectric elastomer actuators (DEAs) face an acknowledged challenge: On the one hand, the majority of elastomers only achieve small electroactive deformation (<20%) in the absence of prestretch; on the other hand, rare elastomers capable of showing large electroactive deformation require relatively complicated processing and chemistry. This work addresses this challenge by fabricating an elastomer with a network of large side groups, which achieves a very large electroactive deformation (218%) without pre‐stretch. This elastomer can be rapidly and massively fabricated within a few min, by polymerizing a commercial monomer with a large alkyl side group. The large side groups in the polymer network repel each other and extend the load‐bearing strands, which results in a pronounced strain‐hardening behavior. This behavior helps the elastomer to get rid of electromechanical instability during actuation and hence to exhibit a large electro‐active deformation, a high energy density (>> human muscle), and a large output force (≈500 times self‐weight). the elastomer capable of manufacturing a soft electroactive gripper is demonstrated with large deformation, large force, and rapid response, which enables grasping fragile objects of various complex shapes in an agile away. [ABSTRACT FROM AUTHOR]

Polymer‐based dielectrics with fast electrostatic energy storage and release, are crucial for advanced electronics and power systems. However, the deterioration of insulation performance and charge–discharge efficiency of polymer dielectrics at elevated temperatures and high electric fields hinder the applications of capacitors in harsh environments. Herein, a facile and scalable approach is reported to fabricating flexible high‐temperature polymer dielectrics for high‐efficiency energy storage by ultraviolet irradiation. The resultant dielectric films exhibit an augment of 493% in energy density and exceeding 800% in discharge efficiency at 200 °C (3.2 J cm−3 and over 90% discharge efficiency at 480 M V−1m for irradiated polyetherimide (PEI), 0.54 J cm−3, and below 10% discharge efficiency at 400 MV m−1 for pristine PEI) and excellent cycle performance. The injected space charge is found to be the dominant contributor to energy loss during the charge–discharge process. Free radicals introduced by ultraviolet irradiation can act as deep traps to capture injected charge and suppress space charge migration. This work clarifies the contribution of space charge to energy loss and demonstrates the effectiveness of ultraviolet irradiation in improving the capacitive performance of high‐temperature polymer dielectrics. These findings provide a novel paradigm for the rational design of high‐temperature polymer dielectrics for high‐efficiency energy storage. [ABSTRACT FROM AUTHOR]

Dielectric elastomer actuator (DEA) is considered as an ideal artificial muscle with soft and light in nature, widespread application in soft robotics and sensors. Dielectric elastomer (DE), the core component of DEA, with high output force and large actuation strain under relatively low driving electric field is critical for high‐performance DEA. However, the widely used VHB series (3M) DE suffered from very large pre‐strain and high driving voltage to get their high actuation performance, limiting their scope of application. In this work, the DEs with good mechanical and dielectric properties were prepared via UV curing method consisting of acrylic acid (AA) with strong polar groups as functional monomer, n‐butyl acrylate (BA) as soft monomer and urethane acrylate as cross‐linker (c‐p(BA‐AA)). The c‐p(BA‐AA) DE films obtained the simultaneous increasing of dielectric constant and breakdown strength with the increasing content of AA, which guaranteed the good actuation performance. The c‐p(BA‐AA) film exhibited excellent actuating performance (44.11% actuation strain at 45 kV/mm) without pre‐strain. Besides, a simple linear actuator based on the c‐p(BA‐AA) film could easily output weight that is tens of times of its own active weight (654.1 mN/g at 30 kV/mm). [ABSTRACT FROM AUTHOR]

As a natural renewable material, wood has good environmental characteristics and is widely used in the fields of architecture, landscapes, furniture and other fields. At present, as the main source of wood, artificial rapid forests generally have disadvantages such as loose structure, low density, low strength, poor size stability, etc., and are prone to deterioration due to external factors. The research on the improvement of the improvement in the improvement of wood antiseptic, hydrophobic, optical resistance, and flame retardant in recent years was reviewed, in order to provide guidance for the combination of wood durable functional combination. [ABSTRACT FROM AUTHOR]

Increasing the actuation characteristics of dielectric elastomer actuators (DEAs) under low electric field strength without compromising the elasticity and breakdown strength is still one of the great challenges in application field. Herein, we propose a simple, efficient, and controllable strategy to prepare dielectric elastomers with intrinsically good integrated properties by introducing styrene ethylene butylene styrene (SEBS) in thermoplastic polyurethane (TPU). Combined with experiments and molecular dynamics simulation, we find that the SEBS is uniformly dispersed in TPU matrix and a good interface structure is formed by pi–pi interaction and entanglement. The above characteristics lead to the destruction of the hydrogen bond network of TPU and the formation of single aggregation structure. Consequently, much decreased Young's modulus (Y) and enhanced breakdown field (Ebr) are achieved. Especially, when the content of SEBS is 4.76 wt%, the blend shows a desirable Y of 2.4 MPa and a much improved Ebr (118 kV mm−1), which is about 59% lower and 42% higher than those of TPU, respectively. As a result, the maximum electrical strain area of the dielectric blend elastomer reaches 4.7%, which is 250% higher than that of pure TPU under the same electric field strength. [ABSTRACT FROM AUTHOR]

The addition‐type liquid silicone rubber (ALSR) co‐filled with spheroidal Al2O3 and flaky BN was prepared by the mechanical blending and hot press methods to enhance the thermal, electrical, and mechanical properties for industrial applications. Morphologies of ALSR composites were observed by scanning electron microscopy (SEM). It was found that the interaction and dispersion state of fillers in the ALSR matrix were improved by the introduction of BN sheets. Thermal, electrical, and mechanical performances of the ALSR composites were also investigated in this work. The result indicated that the thermal conductivity of ALSR can reach 0.64 W m−1 K−1 at the loading of 20 wt% Al2O3/20 wt% BN, which is 3.76 times higher than that of pure ALSR. The addition of Al2O3 particles and BN sheets also improve the thermal stability of ALSR composites. Moreover, pure ALSR and ALSR composites showed relatively lower dielectric permittivity (1.9–3.1) and dielectric loss factor (<0.001) at the frequency of 103 Hz. The insulation properties including volume resistivity and breakdown strength were improved by the introduction of flaky BN in the ALSR matrix. The volume resistivity and characteristic breakdown strength E0 are 6.68 × 1015 Ω m and 93 kV/mm, respectively, at the loading of 20 wt% Al2O3/20 wt% BN. In addition, the mechanical characteristics including elongation at break and tensile strength of ALSR composites were also enhanced by co‐filled fillers. The combination of these improved performances makes the co‐filled ALSR composites attractive in the field of electrical and electronic applications. [ABSTRACT FROM AUTHOR]

Objective To explore the effect of cardiac rehabilitation nursing on negative emotion and cardiac function of patients with myocardial infarction undergoing interventional therapy. Methods 92 patients with myocardial infarction who received interventional therapy in Tongji Hospital Affiliated to Tongji Medical College of Huazhong University of science and technology from February 2019 to February 2020 were randomly divided into a control group and an observation group according to the ratio of 1+ 1. 46 cases in the control group received routine nursing, while the observation group received cardiac rehabilitation nursing on the basis of routine nursing. The emotional state, cardiac function and quality of life of the two groups were compared before and 3 months after nursing. Results After nursing, the scores of SAS and SDS in the two groups were significantly lower than those before nursing in the same group (both P < 0. 05), and the scores in the observation group were significantly lower than those in the control group at the same period (both P <0.05). The left ventricular ejection fraction (LVEF) and cardiac index (CI) in the two groups were significantly higher than those before nursing in the same group (both P < 0. 05), and the scores in the observation group were significantly higher than those in the control group at the same period (both P <0. 05). The scores of GQOLI-74 in the observation group were significantly higher than those in the control group (01 P <0.05$. Conclusion The implementation of cardiac rehabilitation nursing for patients with myocardial infarction after interventional therapy can significantly alleviate the negative emotions of patients, and effectively improve the cardiac function and quality of life. [ABSTRACT FROM AUTHOR]

Leucorryum juniperoideum is a common bryophyte in the southeast china,which is considered to be an ideal ornamental plant used in garden. Nitrogen (N) is a kind of necessary element to plant growth, but excess N can be capable of causing serious injury to the most plants. According to recent studies, the diversity of bryophytes was severely decreased by the more and more increasing N deposition. In order to reveal the growth and physiological responses of L. juniperoideum to the intensification of N deposition, three forms of nitrogen, i.e. lime nitrate (Ca(NO3)2) representing the nitrate N, ammonium bicarbonate (NH4HCO3) representing the ammonium N and ammonium nitrate (NH4HCO3) representing the mixed N, were used in the treatments of simulating N deposition. The gametophyte material used in this experiment was propagated by shattered fragments and cultured in the greenhouse six months ahead of the first fertilization. The gradient of N concentration was 0, 2, 4, 8, 16 gN.m-2 prepared using a solution of lime nitrate, ammonium nitrate and ammonium nitrate respectively. The results showed that the tissue N contents of L. juniperoideum were raised as the increasing of the three kinds of nitrogen concentration and the increasing tissue N contents of Ca(NO3)2. NH4HCO3 and NH4NO3 were 69.1%, 25.7% and 43.1% respectively. The dead plant rate of L. juniperoideum gametophyte also increased as the three kinds of nitrogen fertilization concentration rising, but there are remarkable differences among the three kinds of nitrogen treatments, and the dead plant rate of Ca(NO3)2, NH4HCO3 and NH4NO3 were 16.5%, 12.5% and 13.9% respectively. As well as the net weight of the L. juniperoideum, the plant height came out different as the three kinds of nitrogen concentration rising. The net weight and the plant height all added by the treatments of low concentration NH4HCO3(4 gN.m-2), but not by nitrate N and mixed N treatments, and three kinds of nitrogen treatments all cause the reduction of the net weight and the plant height as the N concentration rising. The changes of the Chlorophyll (a, b) contents by three N treatments all occurred from increase to decrease, but the Chlorophyll (a, b) contents of NH4HCO3treatments were higher than other N forms at the same concentration, and the NH4HCO3 concentration of decreasing Chlorophyll (a, b) content was higher than Ca(NO3)2 and NH4NO3. There existed an obviously similar variation tendency of the superoxide dismutase (SOD) among the three kinds of nitrogen treatments, which increased as the N concentration rising, while the soluble protein content and the praline content increased at lower N concentration and reduced at higher N concentration. These physiological indexes were not synchronous among the three N treatments. It was demonstrated in the experiments that L. juniperoideum was more sensitive to nitrate N than ammonium N, and small ammonium N additions (4 gN.m-2) tended to increased its growth, while nitrate N additions decreased its growth. Therefore, ammonium N could be used as the N source of L. juniperoideum and the low concentration of nitrogen additions was critical to the fertilization of L. juniperoideum. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The RNA-guided Cas9 nuclease from microbial clustered regularly interspaced short palindromic repeats (CRISPR) adaptive immune system has been used to facilitate efficient genome engineering in eukaryotic cells. The specific targeted genome is recognized and cut by gRNA-directed CRISPR/Cas9 complex, specifically by the endonuclease Cas9. The targeted gene locus could be repaired either by homology-directed repair or nonhomologous end joining, thus achieving a desired editing outcome. Viruses infect cells through specific receptors, and then the viral genome is transcribed, replicated and translated to complete its life cycle. As a result, some DNA virus and retrovirus genomes are integrated into the cellular genome. Gene therapy is a new trend to treat viral infected diseases. Given its designable sequence-specific editing of the targeted genome, CRISPR/Cas9 has tremendous potential in treating persistent and latent viral infections. In this review, we summarize the mechanism and progresses of CRISPR/Cas9, and also highlight its therapeutic application in infectious diseases.

Objective: To investigate effect of clinical pathway management on pediatric pneumonia., Method: Data were colleted from children hospitalizated with bronchial pneumonia, bronchiolitis, mycoplasma pneumonia in Center of Respiratory Disorders in Children's Hospital of Chongqing Medical University from January 2011 to December 2012. According to implement of clinical pathway management, all patients were divided into pathway management group (n = 405) and non-pathway management group (n = 503). Length of stay, costs of hospitalization, clinical effect and use of antibiotics were compared in these two groups., Result: In pathway management group, average length of stay of children with bronchial pneumonia and bronchiolitis was (6.1 ± 1.6) d and (6.2 ± 1.5) d respectively. While in non-pathway management group, length of stay was (7.2 ± 1.9) d and (7.3 ± 1.5) d (P = 0.000). There was no significant difference in length of stay between these two groups of children with mycoplasma pneumonia [ (6.9 ± 1.8) d vs.(7.7 ± 2.5) d] (P = 0.198). Costs of auxiliary tests in pathway management group was slightly higher than that in non-pathway management group. While other costs in pathway management group were significantly lower than those in non-pathway management group. Total costs of hospitalization of patients with these three diseases in pathway management group and non-pathway management group were ¥(4609 ± 1225) vs ¥ (5629 ± 1813) , ¥ (5006 ± 1250) vs. ¥ (5686 ± 1337), ¥ (4946 ± 1259) vs. ¥ (6488 ± 3032) respectively. There was a significant difference (P < 0.05). Percentages of antibiotics use in two groups were 70.9% vs.99.4%, 45.7% vs.93.4% and 96.2% vs.100.0%. Antibiotics related indicators such as mean number of day of use, ratio of combination and grade of antibiotics were significantly higher in pathway management group compared to non-pathway management group (P < 0.01). There was no significant difference in other indicators like clinical effect and unscheduled readmission in 30 days between two groups (P > 0.05)., Conclusion: Clinical pathway management can regulate medical behaviors through reduction of medical costs, avoidance of excessive laboratory tests and therapy, and regulation of antibiotic use.

Objective: To investigate the mixed infection and analyze risk factors in children with severe adenovirus pneumonia., Methods: A retrospective analysis was performed on the clinical data of 756 children with adenovirus pneumonia between June 2009 and June 2011. Pathogens and risk factors were studied in 216 severe cases., Results: Of the 216 severe cases, 138 (63.9%) were aged from 6 months to 2 years, and 161 (74.5%) developed the disease in the winter and spring; 177 (81.9%) were affected by 1-4 pathogens besides adenovirus, including 74 cases (34.3%) infected with one pathogen as an addition. A total of 334 pathogen strains were identified from the respiratory secretions and sera of the 216 cases. Of them, 163 (48.8%) were bacterial strains, dominated by Gram-negative bacteria (124 strains), 108 (32.3%) were viral strains, and 40 (12.0%) were fungal strains. Multivariate logistic regression analysis indicated that congenital heart disease, congenital airway abnormalities, nutritional anemia, recurrent pulmonary infection, and surgical history were the independent risk factors for severe adenovirus pneumonia in children, with odds ratios of 3.3, 11.1, 7.2, 14.3 and 12.9 respectively (P<0.05)., Conclusions: Severe adenovirus pneumonia is mostly seen in children aged from 6 months to 2 years and occurs frequently in the winter and spring. Many cases are also infected with other pathogens, most commonly Gram-negative bacteria. Congenital heart disease, congenital airway abnormalities, nutritional anemia, recurrent pulmonary infection and surgical history are the independent risk factors for severe adenovirus pneumonia in children.