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Using ZnO nanowires as needle anodes in gas discharge is helpful for maintaining continuous discharge with a relatively low voltage. It is necessary that the ZnO nanowires are far enough apart to guarantee no electric field weakening and that the nanowire anodes are easy to assemble together with the discharging devices. An AC/DC electric-field-assisted wet chemical method is proposed in this paper. It was used to grow ZnO nanowires directly on discharging devices. The nanowires covered the whole electrode in the case in which only a DC field was applied. Moreover, the tips of the nanowires were scattered, similar to the results observed under the application of AC fields. The average distance between the tips of the highest nanowires was approximately equal to 4 μm, which almost meets the requirement of gas discharge. The research concerning growing ZnO nanowires directly on PCBs shown that, at the current time, ZnO nanowires on PCBs did not meet the requirements of gas discharge; however, in this study, the parameters regarding ZnO nanowire growth were established. [ABSTRACT FROM AUTHOR]

Achieving a high strain under a low electric field is critical for actuator applications, and so is something which has always been pursued. Here, an enhanced strain was achieved by introducing Sr0.7Bi0.2TiO3 (SBT) into Bi1/2(Na0.84K0.16)1/2TiO3 (BNKT) under the guidance of phase boundary engineering and domain design. The introduction of the SBT induces a phase transition from the dominant rhombohedral to the dominant tetragonal and strong relaxor behaviour, as well as increased ergodicity. The enhanced and anti-fatigue strain of 0.57% was obtained in BNKT-8SBT ceramics under a relatively low electric field of 50 kV cm−1, accompanied by a large of 1140 pm V−1. An atomic-resolution displacement vector map reveals the coexistence of R and T nanodomains induced by local structural inhomogeneity. The coexistent nanodomains contribute to a flexible domain structure. This unique domain structure is suggested to be the origin of the relaxor features and the enhanced strains. This result is helpful to understand the excellent performance from a structural point of view and could promote further development of high-performance materials. [ABSTRACT FROM AUTHOR]

Dielectric materials as capacitors with high energy storage performance have received substantial attention for applications as important components in modern electrical and electronic systems. Relaxor ferroelectrics, as one of the popular dielectric materials, have demonstrated extraordinary energy storage performance. However, the origin of this extraordinary performance is not fully understood due to the complex atomic structural heterogeneity. Here, aberration-corrected scanning transmission electron microscopy is employed to study the atomistic structure of a Sr0.7Bi0.2TiO3 lead-free relaxor ferroelectric thin film, which shows high energy density of 77.8 J cm−3, good energy efficiency of 67.8%, and high frequency, temperature and antifatigue stability simultaneously. A slush-like polar structure with 2–4 nm multi-domains and low-angle domain walls, rather than polar nanoregions, is observed, revealed and quantitively described in the Sr0.7Bi0.2TiO3 relaxor ferroelectric thin film. This slush-like polar structure is considered to enable flexible domain switching under an electric field, and is proposed as the mechanism for the high energy storage performance. These results benefit the understanding of the atomic-scale structure of relaxor ferroelectrics and provide guidance for the exploration of new relaxor ferroelectrics with high energy storage performance. [ABSTRACT FROM AUTHOR]

High electrostability and long life-time of planar chip technology are crucial for electrophysiological measurements such as ionic current recording through ion channel proteins embedded in biological cell membrane. In this paper, we propose a novel planar microchip integrated with microelectrochemical cell array toward to a feasible solution for ion channel screening with high resolution and long life-time. In order to reduce the interference from the leakage currents, a synthetic lipid bilayer is applied to form a high sealing resistance. The whole-cell electrical access can be constructed via electroporating the lipid bilayer in close proximity to the cell membrane. Parameters of electroporation including amplitude and time scale are firstly optimized by using parallel electroporation to the lipid bilayers. In this approach, individual cells can be trapped to the target positions by applying dielectrophoresis (DEP) manipulation. Poly(ethylene glycol) (PEG) is employed with low concentration to facilitate the closed contact between the cells and the lipid bilayer to increase the efficiency of the whole-cell mode construction. Through this chip based method, stable current recordings through inward rectifier potassium (Kir) ion channels embedded in rat basophilic leukemia (RBL-1) cell membrane are achieved with high electrical sealing resistance (over 1 GΩ). In addition, without need for complex fluidic connections, this method allows for an easy operation and further miniaturization of the measuring system. [ABSTRACT FROM AUTHOR]

Microbial community composition, function, and viability are important for biofilm-based sewage treatment technologies. Most studies of microbial communities mainly rely on the total deoxyribonucleic acid (DNA) extracted from the biofilm. However, nucleotide materials released from dead microorganisms may interfere with the analysis of viable microorganisms and their metabolic potential. In this study, we developed a protocol to assess viability as well as viable community composition and function in biofilm in a sewage treatment system using propidium monoazide (PMA) coupled with real-time quantitative polymerase chain reaction (qPCR) and metagenomic technology. The optimal removal of PMA from non-viable cells was achieved by a PMA concentration of 4 μM, incubation in darkness for 5 min, and exposure for 5 min. Simultaneously, the detection limit can reach a viable bacteria proportion of 1%, within the detection concentration range of 102–108 CFU/mL (colony forming unit/mL), showing its effectiveness in removing interference from dead cells. Under the optimal conditions, the result of PMA–metagenomic sequencing revealed that 6.72% to 8.18% of non-viable microorganisms were influenced and the composition and relative abundance of the dominant genera were changed. Overall, this study established a fast, sensitive, and highly specific biofilm viability detection method, which could provide technical support for accurately deciphering the structural composition and function of viable microbial communities in sewage treatment biofilms. [ABSTRACT FROM AUTHOR]

Using National Vital Statistics Birth and Fetal Death Data from 1995 to 2020 linked to county-level information on wildfires, we use variation in wildfire timing to examine how effects of wildfire exposure on infant health vary by maternal education. Results indicate that wildfire exposure increases the likelihood of low birth weight and fetal death, but effects vary by both trimester and maternal education. Mediation analyses suggest the variation by maternal education reflects selective survival and unequal sensitivity, rather than differential parental response to wildfires. In addition, mediation analyses suggest that maternal behaviors explain a greater share of the relationship between wildfire exposure and infant health than air quality. Wildfires may therefore reduce infant health through stress. [ABSTRACT FROM AUTHOR]

Hierarchical classification offers a more specific categorization of data and breaks down large classification problems into subproblems, providing improved prediction accuracy and predictive power for undefined categories, while also mitigating the impact of poor-quality data. Despite these advantages, its application in predicting primary cancer is rare. To leverage the similarity of cancers and the specificity of methylation patterns among them, we developed the Cancer Hierarchy Classification Tool (CHCT) using the idea of hierarchical classification, with methylation data from 30 cancer types and 8239 methylome samples downloaded from publicly available databases (The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO)). We used unsupervised clustering to divide the classification subproblems and screened differentially methylated sites using Analysis of variance (ANOVA) test, Tukey-kramer test, and Boruta algorithms to construct models for each classifier module. After validation, CHCT accurately classified 1568 out of 1660 cases in the test set, with an average accuracy of 94.46%. We further curated an independent validation cohort of 677 cancer samples from GEO and assigned a diagnosis using CHCT, which showed high diagnostic potential with generally high accuracies (an average accuracy of 91.40%). Moreover, CHCT demonstrates predictive capability for additional cancer types beyond its original classifier scope as demonstrated in the medulloblastoma and pituitary tumor datasets. In summary, CHCT can hierarchically classify primary cancer by methylation profile, by splitting a large-scale classification of 30 cancer types into ten smaller classification problems. These results indicate that cancer hierarchical classification has the potential to be an accurate and robust cancer classification method. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effects of Salvia miltiorrhiza on cerebral infarction volume, nerve behavior and brain tissue SOD, GSH-Px, MDA, GDNF, BDNF in rats with focal cerebral ischemia reperfusion injury. Methods: Healthy adult male SD rats (clean grade) 80, were randomly divided into sham operation group (saline), model group (saline), low dose group (10 mg/kg salvianolate), high dose group (30 mg/kg salvianolate) and edaravone group (6 mg/ kg) with 16 rats in each groups were compared after operation in rats, 48 h neural behavior of 24 h and 72 h scores, cerebral infarction volume 24 h after operation; SOD, GSH-Px and other indicators of brain tissue of rats after the determination of 72 h. Results: After 24 h, low dose group, high dose group and edaravone group, the cerebral infarction volume were less than the model group, high dose group and edaravone group, the infarct volume was less than the low dose group; after 24 h, 48 h, 72 h, scores of neurological behavior in the low dose group and high dose group and Yidala in the study group were lower than model group, neural behavior in high dose group and edaravone group scores were lower than the low dose group; low dose group, high dose group and edaravone group in the brain tissue of SOD, GSH-Px, BDNF, GDNF were higher than that of model group, and MDA was lower than that of model group; high dose group and edaravone group in the brain tissue of SOD, GSH-Px, BDNF, GDNF were higher than those in the low dose group, and MDA was lower than that of low dose group. Conclusion: The treatment of focal cerebral ischemia reperfusion injury in rats by inhibiting lipid peroxidation, protecting Magnesium Oxide's activity, thereby reaching the therapeutic effect. [ABSTRACT FROM AUTHOR]