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High-intensity human activities have caused dramatic transformations of land function in China's coastal zone, putting enormous pressure on the region's ecological environment. It is urgent to fully understand the spatiotemporal evolution of the land-use function in the coastal zone to promote sustainable development. Therefore, based on CNLUCC data for 2000, 2010, and 2020, this study quantitatively explored the spatiotemporal evolution of production–living–ecological land (PLEL) and its eco-environmental response in China's coastal zone by using multiple land-use analysis methods, gradient analysis, and the eco-environmental quality index. The results showed that over the past 20 years, the production land (PL) continued to decrease, whereas the living land (LL) and blue ecological land (BEL) increased. In the vertical direction, PL and the ecological land (EL) dominated in the northern and the southern coastal zone, respectively. In the horizontal direction, with increasing distance from the coastline, the green ecological land (GEL) increased, whereas it was the opposite for BEL. The transformations of PLEL were high and low frequency in the north and south, respectively. From 2000 to 2020, the eco-environmental quality of China's coastal zone slightly degraded, with conditions that were "excellent in the south and poor in the north". The eco-environmental qualities of each sub-coastal zone gradually improved with increasing distance from the coastline. The main transformation types that led to eco-environmental improvement and degradation were from other production lands (OPL) to blue ecological land (BEL) and BEL to OPL, respectively. The findings will guide PLEL planning, eco-environmental protection, and science-based land usage. [ABSTRACT FROM AUTHOR]

Existing research on the magnetic coupler of unmanned aerial vehicle (UAV) wireless charging systems usually ignores the UAV fuselage, but the fuselage causes eddy current loss and reduces a system's efficiency. Therefore, aiming at the above problems, this paper proposes a design for a magnetic coupler using nanocrystalline cores to reduce the loss caused by the UAV fuselage. First, the parameters of the asymmetric circular coils were designed for higher mutual inductance. The losses caused by the windings and cores were also calculated. Second, for the loss effect of the carbon fiber fuselage, the fuselage was modeled as an additional coil coupled with both the transmitting and receiving coils. The fact that the eddy current induced by the fuselage leads to efficiency reduction is revealed, which has been generally ignored by previous research. Then, the effect of the nanocrystalline alloy was analyzed based on the magnetic circuit model. An optimized nanocrystalline alloy film was applied to reduce eddy current loss and improve coupler efficiency. Finally, an experimental prototype with a 500 W output, 90.3% efficiency, and a 300 mm air gap were fabricated. When compared to the design without UAV material considerations, the coupler efficiency was improved by 7.9%. [ABSTRACT FROM AUTHOR]

Objective To study the expression and clinical significance of long non-coding RNA (LncRNA) FEZF1- AS1 and microRNA (miR)-610 in the bladder cancer tissues. Methods The real-time quantitative PCR (qRT-PCR) was used to detect the expression of LncRNA FEZF1-AS1 and miR-610 in 79 cases of bladder cancer tissues and 40 cases of normal bladder mucosa tissues. The expression differences between groups in LncRNA FEZF1-AS1, miR-610 and their relationship with clinicopathological features were analyzed statistically. Results Compared with the normal bladder mucosa, the relative expression of LncRNA FEZF1-AS1 was significantly higher in the bladder cancer tissues, while the relative expression of miR-610 was significantly lower (both P <0.05). The expression of LncRNA FEZF1-AS1 and miR-610 in the cancer tissues was related to tumor staging and degree of tissue differentiation (all P <0.05), but not to age, gender, tumor size, number, depth or lymph node metastasis (all P >0.05). There was a significant negative correlation between LncRNA FEZF1-AS1 and miR-610 expression in the cancer tissues (r = -0.611, P = 0.000). Conclusion The expression of LncRNA FEZF1-AS1 increases and the expression of miR-610 decreases in the bladder cancer tissues, and detection of their expression helps to determine the condition of bladder cancer. [ABSTRACT FROM AUTHOR]

Efficient and accurate access to coastal land cover information is of great significance for marine disaster prevention and mitigation. Although the popular and common sensors of land resource satellites provide free and valuable images to map the land cover, coastal areas often encounter significant cloud cover, especially in tropical areas, which makes the classification in those areas non-ideal. To solve this problem, we proposed a framework of combining medium-resolution optical images and synthetic aperture radar (SAR) data with the recently popular object-based image analysis (OBIA) method and used the Landsat Operational Land Imager (OLI) and Phased Array type L-band Synthetic Aperture Radar (PALSAR) images acquired in Singapore in 2017 as a case study. We designed experiments to confirm two critical factors of this framework: one is the segmentation scale that determines the average object size, and the other is the classification feature. Accuracy assessments of the land cover indicated that the optimal segmentation scale was between 40 and 80, and the features of the combination of OLI and SAR resulted in higher accuracy than any individual features, especially in areas with cloud cover. Based on the land cover generated by this framework, we assessed the vulnerability of the marine disasters of Singapore in 2008 and 2017 and found that the high-vulnerability areas mainly located in the southeast and increased by 118.97 km 2 over the past decade. To clarify the disaster response plan for different geographical environments, we classified risk based on altitude and distance from shore. The newly increased high-vulnerability regions within 4 km offshore and below 30 m above sea level are at high risk; these regions may need to focus on strengthening disaster prevention construction. This study serves as a typical example of using remote sensing techniques for the vulnerability assessment of marine disasters, especially those in cloudy coastal areas. [ABSTRACT FROM AUTHOR]

Rapid and accurate updating of urban land areas is of great significance to the study of environmental changes. Although there are many urban land products (ULPs) at present, such as GlobeLand30, Global Urban Footprint (GUF), and Global Human Settlement Layer (GHSL), these products are all static data of a certain year, and are not able to provide high-accuracy updating of urban land areas. In addition, the accuracies of these data and their application value in the update of urban land areas need to be urgently proven. Therefore, we proposed an approach to quickly and accurately update urban land areas in the Kuala Lumpur region of Malaysia, and assessed the accuracies of urban land products in different urban landscape patterns. The approach combined the advantages of multi-source data including existing ULPs, OpenStreetMap (OSM) data, Landsat Operational Land Imager (OLI), and Phased Array type L-band Synthetic Aperture Radar (PALSAR) images. Three main steps make up this approach. First, the urban land training samples were selected in the urban areas consistent with GlobeLand30, GUF, and GHSL, and samples of bare land, vegetation, water bodies, and road auxiliary data were obtained by GlobeLand30 and OSM. Then, the random forest was used to extract urban land areas according to the object's features in the OLI and PALSAR images. Last, we assessed the accuracies of GlobeLand30, GUF, GHSL, and the results of this study (ULC) by using point and area validation methods. The results showed that the ULC had the highest overall accuracy of 90.18% among the four products and could accurately depict urban land in different urban landscapes. The GHSL was the second most accurate of the four products, and the accuracy in urban areas was much higher than that in rural areas. The GUF had many omission errors in urban land areas and could not delineate a large area of complete spatial information of urban land, but it could effectively extract scattered residential land with small patches. GlobeLand30 had the lowest accuracy and could only express rough, large-scale urban land. The above conclusions provide evidence that ULPs and the approach proposed in this study have a great application potential for high-accuracy updating of urban land areas. [ABSTRACT FROM AUTHOR]

As China's coal mines have transitioned to deep mining, the ground stress within the coal seams has progressively increased, resulting in reduced permeability and poor wetting ability of conventional wetting agents. Consequently, these agents have become inadequate in fulfilling the requirements for preventing washouts during deep mining operations. In response to the aforementioned challenges, a solution was proposed to address the issues by formulating a composite wetting agent. This composite wetting agent combines a conventional surfactant with a chelating agent called tetrasodium iminodisuccinate (IDS). By conducting a meticulous screening of surfactant monomer solutions, the ideal formulation for the composite wetting agent was determined by combining the monomer surfactant with IDS. Extensive testing, encompassing evaluations of the composite solution's apparent strain, contact angle measurements, and alterations in the oxygenated functional groups on the coal surface, led to the identification of the optimal composition. This composition consisted of IDS serving as the chelating agent and fatty alcohol polyoxyethylene ether (JFCS).Subsequent assessment of the physical and mechanical performance of the coal briquettes treated with the composite wetting agent revealed notable enhancements. These findings signify significant advancements in the field and hold promising implications. Following the application of the composite wetting agent, notable reductions were observed in the dry basis ash and dry basis full sulfur of coal. Additionally, the water content within the coal mass increased significantly, leading to a substantial enhancement in the wetting effect of the coal body. This enhanced wetting effect effectively mitigated the coal body's inclination towards impact, thereby offering technical support for optimizing water injection into coal seams and preventing as well as treating impact ground pressure. [ABSTRACT FROM AUTHOR]

Wireless charging technology has become an important development trend in future electric vehicle (EV) power supply technology due to its safety, flexibility, and convenience. With its industrialized development, interoperability has become an essential technical link. The interoperability of wireless charging systems refers to the ability of output performance to meet specified indicators when different transmitter and receiver devices are matched. This study reviews the research status of the interoperability of EV wireless charging technology. First, the definition and composition of the interoperability of wireless charging systems are briefly given. Then, the article provides a review of standards about interoperability so far. The interoperability of various magnetic couplers and compensation topologies is also analyzed and summarized. After that, the paper reviews the existing interoperability evaluation methods. Finally, this work highlights the existing problems and challenges in current research of interoperability. We hope that this work will contribute to the further development of EV wireless charging technology. [ABSTRACT FROM AUTHOR]

The double-sided inductor capacitor capacitor topology has been proposed in some national standards for wireless charging systems. However, misalignment between the transmitting and receiving coils usually leads to detuning and weak coupling, resulting in low output power and inefficiency. To improve power output under weak coupling, this article proposes a control method based on the variable inductor and capacitor (VLC). First, it is deduced that the zero phase angle input and full output power can be achieved by VLC regulation under certain misalignment. Second, the variable inductor using an EE-shaped core and pulsewidth modulation controlled capacitor are applied to achieve VLC regulation, and the principles and implementation of VLC are analyzed. Third, as the coupling coefficient k can be identified through the primary electrical parameters, a convenient and accurate coupling coefficient identification method is utilized to help VLC regulation. Finally, a prototype with a 3.3 kW output power and an 87.5% maximum system efficiency (dc–dc) is built to validate the proposed method. The experimental results are consistent with the theoretical analysis, proving that the output power is almost constant when k varies from 0.08 to 0.18. [ABSTRACT FROM AUTHOR]

Sanduao is an important sea-breeding bay in Fujian, South China and holds a high economic status in aquaculture. Quickly and accurately obtaining information including the distribution area, quantity, and aquaculture area is important for breeding area planning, production value estimation, ecological survey, and storm surge prevention. However, as the aquaculture area expands, the seawater background becomes increasingly complex and spectral characteristics differ dramatically, making it difficult to determine the aquaculture area. In this study, we used a high-resolution remote-sensing satellite GF-2 image to introduce a deep-learning Richer Convolutional Features (RCF) network model to extract the aquaculture area. Then we used the density of aquaculture as an assessment index to assess the vulnerability of aquaculture areas in Sanduao. The results demonstrate that this method does not require land and water separation of the area in advance, and good extraction can be achieved in the areas with more sediment and waves, with an extraction accuracy >93%, which is suitable for large-scale aquaculture area extraction. Vulnerability assessment results indicate that the density of aquaculture in the eastern part of Sanduao is considerably high, reaching a higher vulnerability level than other parts. [ABSTRACT FROM AUTHOR]

• The construction and optimization of ecological networks in urban–rural areas are carried out. • A novel comprehensive ecological network optimization strategy with spatial zoning and multi-scenario coupling is proposed. • The optimized ecological network is conducive to promoting the circulation of ecological processes between urban and rural gradients. • The optimization strategy can guarantee the maximization of the integrated benefits of regional urbanization and ecological protection. Ecological network construction and optimization is an effective way to balance the contradiction between regional development and ecological protection in the process of urbanization. The urban–rural fringe is both a frontier zone in the direction of urban expansion and an important space for improving the urban ecological environment. However, there are few studies on how to construct and optimize the ecological networks in urban–rural fringe. In this paper, the morphological spatial pattern analysis (MSPA) and the minimum cumulative resistance model (MCR) were firstly employed to initially construct the ecological network and reveal the characteristics and problems of ecological security pattern in the study area. Then, a new ecological network optimization strategy with a multi-scenario coupling of urban–rural gradient spatial zoning was proposed to meet the maximization of integrated benefits of future urban development and ecological protection. The study results show that: (1) Urbanization caused a high fragmentation of ecological patches, and exerted a strong spatial hindrance to ecological processes. (2) The spatial distribution of the initially constructed ecological network was extremely uneven, and ecological communication in the north–south direction was severely difficult. The optimized ecological network was significantly improved in this respect, and the priority construction of important corridors will also help to strengthen ecological communication in the direction of urban–rural gradient. (3) The proposed optimization strategy improved the connectivity and accessibility of the ecological network in Licheng District, and enhanced its structure, which will promote the overall ecological process cycle and better balanced the urban development and ecological protection. (4) Policy makers should strengthen the construction and implementation of ecological green corridors and forest belts in urban–rural fringe to achieve a balance between urban development and ecological protection. This study can provide scientific references for biodiversity conservation, green infrastructure planning, and sustainable development in the process of urbanization. [ABSTRACT FROM AUTHOR]

Automatic updating of land use/cover change (LUCC) databases using high spatial resolution images (HSRI) is important for environmental monitoring and policy making, especially for coastal areas that connect the land and coast and that tend to change frequently. Many object-based change detection methods are proposed, especially those combining historical LUCC with HSRI. However, the scale parameter(s) segmenting the serial temporal images, which directly determines the average object size, is hard to choose without experts’ intervention. And the samples transferred from historical LUCC also need experts’ intervention to avoid insufficient or wrong samples. With respect to the scale parameter(s) choosing, a Scale Self-Adapting Segmentation (SSAS) approach based on the exponential sampling of a scale parameter and location of the local maximum of a weighted local variance was proposed to determine the scale selection problem when segmenting images constrained by LUCC for detecting changes. With respect to the samples transferring, Knowledge Transfer (KT), a classifier trained on historical images with LUCC and applied in the classification of updated images, was also proposed. Comparison experiments were conducted in a coastal area of Zhujiang, China, using SPOT 5 images acquired in 2005 and 2010. The results reveal that (1) SSAS can segment images more effectively without intervention of experts. (2) KT can also reach the maximum accuracy of samples transfer without experts’ intervention. Strategy SSAS + KT would be a good choice if the temporal historical image and LUCC match, and the historical image and updated image are obtained from the same resource. [ABSTRACT FROM AUTHOR]

• A numerical model of hydraulic fracture height layer-through propagation based on 3D lattice method is carried out, and the influence laws of different parameters on fracture propagation are given by the fracture morphology. • In the formation with low elastic modulus, the fracture is easy to propagate along the width direction; In the formation with high elastic modulus, the fracture is easy to grow in the height direction. • The fracture morphology of high viscosity fracturing fluid is close to circular, while that of the low viscosity fracturing fluid is close to an ellipse. Unconventional reservoirs such as shale and coal rock are generally well-bedded, with significant differences in the interlayer stress and rock physical parameters. The change law of the fracture morphology is difficult to predict after the layer-through propagation of the fracture height during the fracturing operation. Existing studies have widely used multilayered two-dimensional fracture height models, which are not suitable for fracture propagation simulation in unconventional reservoirs under complex geological conditions. This study established a fracture height propagation model based on the three-dimensional (3D) discrete lattice method and used the Xsite software to simulate the layer-through propagation in layered strata under the influence of in-situ stress, rock physical properties, and construction parameters. The effects of different factors on the fracture height and fracture morphology are described. Sensitivity analysis for different model cases revealed that, when the fractures entered a formation with high in-situ stress and fracture toughness, the growth of the fracture height was restrained. As the elastic modulus of the rock increased, the fracture width significantly decreased and the fracture height increased. Increasing the fracturing fluid displacement benefits the growth of the fracture height and width, and accelerates the passage of hydraulic fracture through the interlayer interface to achieve deep penetration reconstruction in the longitudinal direction of the reservoir. Higher fracturing fluid viscosity increases the fracture width and reduces the fracture reconstruction volume, and the fracture morphology changes under different fracturing fluid viscosity. This study is useful for improving and supplementing unconventional reservoir fracture height simulation technology. [ABSTRACT FROM AUTHOR]

• Improve the permeability and water injection effect by dissolving the minerals in coal for the first time. • Choosing iminodisuccinate tetrasodium as water injection additive is environmentally friendly and cheap. • The mechanism of chelating ligands promoting mineral dissolution and improving permeability is given. • Determine the contribution of changing pore structure to disaster prevention and control. Coal seam water injection technology which provides a guarantee for coal mine safety production is significant for the prevention and control of coal mine disasters. The selection of additives is very important for the implementation of coal seam water injection technology. Although the research on additives has been extensive in recent years, the mechanism of additives which can increase the permeability of coal and change mechanical properties of coal is still unclear. After selecting the chelating agent as the water injection additive, we characterized the pore structure of coal by low temperature N 2 adsorption, mercury injection, scanning electron microscopy, etc., and tested the strength of coal by uniaxial hydraulic testing machine, as a result, several interesting results were found. Firstly, the minerals in the coal seam will damage the permeability of the coal seam and impede the flow of water in the coal seam. Secondly, the chelating ligand can interact with minerals like calcite and dolomite. When the concentration of the chelating agent is 500 mg/L, Ca2+ can be detected in the immersion solution and the leaching concentration of Ca2+ is 43.76 times greater than that in the ultra-pure water immersion solution. The change of pH has a greater impact on the leaching concentration of Fe and Mg, while the change of solid–liquid ratio has a smaller impact on their leaching concentration. Thirdly, as the dissolution of minerals, the size and volume of pore in coal increase, specific surface area decrease, connectivity of pore become better, the permeability of coal increase by an average of 129%, which has a promoting effect on water injection. Fourthly, the existence of minerals will affect the mechanical strength of coal. The uniaxial compressive strength of coal decreases after the chelating ligands interacted with the coal and the pH of the solution and soaking time also obviously affect the strength of coal. These results are helpful to open up a new direction for the selection of water injection additives that can realize the green and safe mining of coal. [ABSTRACT FROM AUTHOR]

In this study, efficient knock-in (KI) of human epidermal growth factor (hEGF) cDNA at the ovalbumin (OV) locus in cultured chicken cells was achieved using adenovirus as a delivery for CRISPR/Cas9 elements and optimizing donor vector construction. The strategy of recruiting donor DNA to the insertion site further improved the KI efficiency. The inserted hEGF cDNA can expressed in primary oviduct cells and secreted hEGF promoted proliferation of Hela cells. Moreover, we achieved efficient KI in blastoderm cells without altering their induction in vitro and obtained germline chimeric KI chicken embryos by transplanting KI blastoderm cells as well as injecting adenovirus directly, in vivo. Our results provided an efficient KI method for chicken cells and embryos, and lay the foundation for more convenient production of KI chicken at the OV locus, which will promote the development of oviduct-specific bioreactor. [ABSTRACT FROM AUTHOR]

Information, especially spatial distribution data, related to coastal raft aquaculture is critical to the sustainable development of marine resources and environmental protection. Commercial high spatial resolution satellite imagery can accurately locate raft aquaculture. However, this type of analysis using this expensive imagery requires a large number of images. In contrast, medium resolution satellite imagery, such as Landsat 8 images, are available at no cost, cover large areas with less data volume, and provide acceptable results. Therefore, we used Landsat 8 images to extract the presence of coastal raft aquaculture. Because the high chlorophyll concentration of coastal raft aquaculture areas cause the Normalized Difference Vegetation Index (NDVI) and the edge features to be salient for the water background, we integrated these features into the proposed method. Three sites from north to south in Eastern China were used to validate the method and compare it with our former proposed method using only object-based visually salient NDVI (OBVS-NDVI) features. The new proposed method not only maintains the true positive results of OBVS-NDVI, but also eliminates most false negative results of OBVS-NDVI. Thus, the new proposed method has potential for use in rapid monitoring of coastal raft aquaculture on a large scale. [ABSTRACT FROM AUTHOR]