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The coastline of the Yellow River Delta has undergone significant alterations due to fluctuations in fluvial water and sediment conditions. To analyze changes in the coastline of the Yellow River Delta from 1976 to 2020, this study considered the effects of various factors, such as tide levels, water calculation indices, and high and low tide stages on coastline extraction. Coastlines were extracted utilizing tools like ArcGIS and ENVI, and the Digital Shoreline Analysis System was used to quantify the coastline characteristics. The study found that selecting remote sensing images with good imaging quality and similar tide levels during the ebb phase, along with the use of the Modified Normalized Difference Water Index for calculation, resulted in higher accuracy in coastline extraction. Based on the extracted coastline data, it was found that the coastline of the Yellow River Delta has undergone spatio-temporal variations. The Shenxiangou-Diaokouhe lobe coastline has been eroding since 1976, while the coastline from Dongying port to Gudong oilfield has remained stable since the 1990s due to an artificial seawall for protection. The changes in the coastline near the estuary were found to be related to the amount of fluvial sediment. When there was enough sediment, the coastline tended to accumulate or deposit, while it eroded and retreated when there wasn't enough sediment. Other factors, such as deltaic channel avulsions and oceanic dynamics, also had an impact on the coastline of the Yellow River Delta. The findings of this study can serve as valuable guidance for future comprehensive management planning of the Yellow River Delta. [ABSTRACT FROM AUTHOR]

To evaluate the effect of external diaphragmatic pacing (EDP) combined with inspiratory muscle training on respiratory function in post-stroke patients. Patients with stroke were enrolled from the First Affiliated Hospital of Soochow University in China between 2021 and 2022. The patients were randomized into an EDP treatment group (control group) or an EDP treatment plus inspiratory muscle training group (experimental group). Each therapy was administered once a day for 6 days per week. The peak inspiratory flow (PIF), maximal inspiratory pressure (MIP), forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), FEV1/FVC% ratio, and diaphragm thickness and mobility were measured and compared between the two groups after 4 weeks. After 4 weeks of intervention, respiratory muscle function indicators including PIF (95% CI: 0.21–1.28, p = 0.008) and MIP (95% CI: 6.92–25.44, p = 0.001) significantly improved in the experimental group. Diaphragmatic thickness also significantly increased in the experimental group (p < 0.05), while diaphragmatic excursion showed no significant difference between the two groups. Additionally, FVC (95% CI: 0.14–1.14, p = 0.013) and FEV1 (95% CI: 0.20–1.06, p = 0.005) demonstrated a significant increase in the experimental group, whereas FEV1/FVC% (95% CI: −0.84 to 9.36, p = 0.099) exhibited no significant group difference. EDP combined with inspiratory muscle training in individuals with stroke provides greater benefits than EDP alone in terms of respiratory function recovery, except for the parameters of diaphragmatic excursion and FEV1/FVC%. [ABSTRACT FROM AUTHOR]

Thermally conductive polymeric composites with low dielectric constant are highly promising for the packaging materials in the field of modern communication. Therefore, the synergistic improvement of low dielectric constant and high thermal conductivity has become a current research hotspot. In this work, we propose a one‐step alkylation of boron nitride nanosheet (BNNS) with ultrasonic stratification using 1‐hexanol, and then hot press the films to make Alkyl‐BNNSs orient in the fluorinated polyimide (f‐PI). The resulting Alkyl‐BNNS/f‐PI composite successfully realizes the synergistic improvement of thermal property and dielectric properties, exhibiting a high heat conductivity coefficient of 2.36 Wm−1 K−1 with a filler content of 4.99 wt.%. Moreover, the permittivity and dielectric loss of the film are as low as 1.76 and 0.0065 at 1 MHz, respectively. This work provides a facile strategy for breaking the bottleneck of making polyimide composites simultaneously with high thermal conduction and low dielectric performance. Highlights: The composite exhibits a high heat‐conducting coefficient of 2.36 Wm−1 K−1.Ultra‐low dielectric constant of 1.76 was achieved by the modification of film.Excellent breakdown resistance and flexibility were endowed with the composites. [ABSTRACT FROM AUTHOR]

The inherent balance between dielectric constant and loss restricts the actual usage of dielectric elastomer actuators with high actuation strains, proposing a method that can break this trade‐off has been an urgent query. In this work, silica‐loaded carbon nanotubes (called SiO2@CNT) were prepared as dopants for acrylic resin elastomers (abbreviated as ARE) using the sol–gel method, and the obtained SiO2@CNT/ARE composites reached a dielectric constant of 282.5 at 100 Hz at a filler content of 3.22 vol%, which is 86 times higher than that of the pure ARE, whereas the dielectric loss remains at 0.17. The equilibrium between dielectric constant and loss is broken mainly based on the loading of SiO2 which inhibits the formation of carbon nanotube conductive network and concurrently reinforces the compatibility of the filler with ARE. Such a design offers a generalizable strategy for the subsequent preparation of polymer‐based composite films with excellent dielectric properties. Highlights: Preparation of fillers with excellent dispersibility in the organic phase.The ARE‐based composites exhibit excellent dielectric properties at 100 Hz.The mechanism of increase in dielectric constant is explained using two models. [ABSTRACT FROM AUTHOR]