Rapidly developing remote sensing technology provides massive data for urban planning, mapping, and disaster management. As a carrier of human productive activities, buildings are essential to both ...urban dynamic monitoring and suburban construction inspection. Fully-convolutional-network-based methods have provided a paradigm for automatically extracting buildings from high-resolution imagery. However, high intraclass variance and complexity are two problems in building extraction. It is hard to identify different scales of buildings by using a single receptive field. For this purpose, in this article, we use the stable encoder- decoder architecture, combined with a grid-based attention gate and atrous spatial pyramid pooling module, to capture and restore features progressively and effectively. A modified ResNet50 encoder is also applied to extract features. The proposed method could learn gated features and distinguish buildings from complex surroundings such as trees. We evaluate our model on two building datasets, WHU aerial building dataset and our DB UAV rural building dataset. Experiments show that our model outperforms other five most recent models. The results also exhibit great potential for extracting buildings with different scales and validate the effectiveness of deep learning in practical scenarios.
Higher derivative terms in the gravitational action are natural from the perspective of quantum gravity, but are perceived as leading to a lack of well-posedness. The Gauss–Bonnet term has ...second-order equations of motion, but does not impact gravitational dynamics in 4D, so one might expect that it is not physically relevant. We discuss how signatures can show up in tunnelling processes and whether these will likely be physically accessible in Higgs vacuum decay.
Recently, a number of papers have claimed that the horizon area-and thus the entropy-of near extremal black holes in anti-de Sitter spacetimes can be reduced by dropping particles into them. In this ...paper, we point out that this is a consequence of an underlying incorrect assumption that the energy of an infalling particle changes the internal energy of the black hole by the same amount, whereas actually it is the mass or enthalpy of the black hole that increases by the energy of the particle absorbed.
Covalent adaptable networks (CANs; also known as dynamic covalent networks or vitrimers) are appealing for developing simple and efficient techniques for recycling thermosetting polymers. In this ...paper, ethylene glycol (EG) is used as a solvent to enable pressure-free surface welding, surface repair, and recycling of a malleable epoxy where the transesterification-type bond exchange reaction (BER) imparts a dynamic nature to the covalent network. At a high temperature, the EG molecules participate in the BER, leading to dissolution of the epoxy network. If the EG is allowed to evaporate, the dissolved epoxy can re-form into a solid. The effects of EG content, temperature, and catalyst concentration on EG-assisted BERs are investigated. It is found that the amount of EG can be adjusted to tune the solution/solid transformation: An excessive amount of EG is required to dissolve the epoxy; on the other hand, a shortage of EG can shift the reaction back to re-form the polymer. Furthermore, the catalyst concentration defines the point at which dissolution initiates, while the degradation rate depends on temperature. This new EG-assisted method is further used for surface welding, surface damage repair, and powder-based reprocessing. The EG-assisted method does not require pressure and can achieve the properties of a fresh sample. It also provides potential opportunities to develop facile recycling techniques for thermosetting polymers.
The rapid development in deep learning and computer vision has introduced new opportunities and paradigms for building extraction from remote sensing images. In this paper, we propose a novel fully ...convolutional network (FCN), in which a spatial residual inception (SRI) module is proposed to capture and aggregate multi-scale contexts for semantic understanding by successively fusing multi-level features. The proposed SRI-Net is capable of accurately detecting large buildings that might be easily omitted while retaining global morphological characteristics and local details. On the other hand, to improve computational efficiency, depthwise separable convolutions and convolution factorization are introduced to significantly decrease the number of model parameters. The proposed model is evaluated on the Inria Aerial Image Labeling Dataset and the Wuhan University (WHU) Aerial Building Dataset. The experimental results show that the proposed methods exhibit significant improvements compared with several state-of-the-art FCNs, including SegNet, U-Net, RefineNet, and DeepLab v3+. The proposed model shows promising potential for building detection from remote sensing images on a large scale.
Background: Macrophages and neutrophils are key phagocytes in regeneration.
Results: Neutrophils are the primary phagocytes in the inflammatory stage and are dispensable for zebrafish fin ...regeneration, whereas macrophages mainly function in the resolution stage and are required for fin regeneration.
Conclusion: Macrophages and neutrophils behave differently during zebrafish fin injury and regeneration.
Significance: Our study documents that macrophages and neutrophils play distinct functions in tissue regeneration.
Macrophages and neutrophils are the pivotal immune phagocytes that enter the wound after tissue injury to remove the cell debris and invaded microorganisms, which presumably facilitate the regrowth of injured tissues. Taking advantage of the regeneration abilities of zebrafish and the newly generated leukocyte-specific zebrafish lines with labeling of both leukocyte lineages, we assessed the behaviors and functions of neutrophils and macrophages during tail fin regeneration. Live imaging showed that within 6 hours post amputation, the inflammatory stage, neutrophils were the primary cells scavenging apoptotic bodies and small cell debris, although they had limited phagocytic capacity and quickly underwent apoptosis. From 6 hours post amputation on, the resolution and regeneration stage, macrophages became the dominant scavengers, efficiently resolving inflammation and facilitating tissue remodeling and regrowth. Ablation of macrophages but not neutrophils severely impaired the inflammatory resolution and tissue regeneration, resulting in the formation of large vacuoles in the regenerated fins. In contrast, removal of neutrophils slightly accelerates the regrowth of injured fin. Our study documents the differing behaviors and functions of macrophages and neutrophils during tissue regeneration.
Thermosetting polymers and composites are a class of high-performance materials with significant industrial applications. However, recycling of thermosets and their filling matters are significantly ...challenging. Here, we propose a method to recycle epoxy thermosetting polymer and composites efficiently by a synergistic effect of a solvent mixture using a highly efficient organic catalyst at an ordinary pressure and mild temperatures. The anhydride-epoxy network depolymerization enabled by selective ester bond cleavage process is substantially enhanced by a good solvent assisted and alcohol participated transesterification reaction. The epoxy thermoset can be dissolved in 28 min with 50% mass loss, and 70 min with 95% mass loss at 170 °C under ambient pressure. We demonstrate that this method can be used to reclaim carbon fibers from industrial reinforced epoxy composite products and embedded metal parts from commercial electronic products with undiminished properties at a mild temperature (∼170 °C) under an ordinary pressure in a short time (1.5 h). Moreover, the decomposed epoxy oligomer can be reused as a reactive ingredient for the preparation of new epoxy materials with high strength and modulus. This work provides a new insight into the thermosets dissolution and recycling.
Abstract Zinc (Zn) and silver (Ag) are co-implanted into titanium by plasma immersion ion implantation. A Zn containing film with Ag nanoparticles (Ag NPs) possessing a wide size distribution is ...formed on the surface and the corrosion resistance is improved due to the micro-galvanic couples formed by the implanted Zn and Ag. Not only are the initial adhesion, spreading, proliferation and osteogenic differentiation of rBMSCs observed from the Zn/Ag implanted Ti in vitro , but also bacteria killing is achieved both in vitro and in vivo . Electrochemical polarization and ion release measurements suggest that the excellent osteogenic activity and antibacterial ability of the Zn/Ag co-implanted titanium are related to the synergistic effect resulting from the long-range interactions of the released Zn ions and short-range interactions of the embedded Ag NPs. The Zn/Ag co-implanted titanium offers both excellent osteogenic activity and antibacterial ability and has large potential in orthopedic and dental implants.
Lung cancer is a malignant tumor with high rates of mortality and shows significant hereditary predisposition. Previous genome-wide association studies suggest that rs748404, located at promoter of ...TGM5 (transglutaminase 5), is associated with lung carcinoma. By analysis of 1000 genomes project data for three representative populations in the world, another five SNPs are identified to be in strong linkage disequilibrium with rs748404, thus suggesting that they may also be associated with lung carcinoma risk. However, it is ambiguous about the actually causal SNP(s) and the mechanism for the association. Dual-luciferase assay indicates that the functional SNPs are not rs748404, rs12911132 or rs35535629 but another three SNPs (rs66651343, rs12909095 and rs17779494) in lung cell. By chromosome conformation capture, it is disclosed that the enhancer encompassing the two SNPs, rs66651343 and rs12909095, can interact with the promoter of CCNDBP1 (cyclin D1 binding protein 1). RNA-seq data analysis indicates that CCNDBP1 expression is dependent on the genotype of these two SNPs. Chromatin immunoprecipitation assay suggests that the fragments spanning rs66651343 and rs12909095 can bind with the transcription factors, cut like homeobox 1 and SRY-box transcription factor 9, respectively. Our results establish the connection between genetic variations at this locus and lung cancer susceptibility.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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