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AbstractThis research constructs an index system to measure the level of high-quality development of service industry in Chinese cities at the prefecture-level, and uses the entropy-weighted TOPSIS method to measure it. The spatial convergence model is also used to analyze the spatial and temporal convergence of service industries in urban agglomerations, and to analyze their regional differences and spatial and temporal convergence characteristics. It is found that there are regional differences in the level of service industry development in Chinese cities, showing conditional beta convergence characteristics. Further, the convergence of high-quality development of service industry is decomposed in the dimension of five intrinsic factors of high-quality industrial development. It is concluded that the spatial-temporal convergence presented by the high-quality development of service industry mainly comes from industrial restructuring, industrial synergy development and industrial environment optimization. The results show that the institutional factors of “active government” and “efficient market” significantly contribute to the improvement of the quality development of urban services, after add the institutional factors of fiscal decentralization and marketization. And the research based on spatial spillover effects find that the convergence of service development among cities is mainly based on the “Yardstick Competition” of convergence. These results contribute to a comprehensive understanding of the level of quality development of China’s urban service industry, also provide a reference for policy formulation for coordinated regional development and the construction of a unified national market. [ABSTRACT FROM AUTHOR]

• The crack propagation process and its strain evolution were captured using the split Hopkinson pressure bar (SHPB) device combined with high-speed digital image processing. • The relationship between dynamic mode Ⅰ fracture toughness and crack propagation velocity of bedding shale with bedding and loading rate was analyzed qualitatively and quantitatively. • Based on the Traction-Separation Law, the method of global cohesive element was used to simulate the dynamic crack propagation and calculate the fracture toughness of bedding shale. The fracture behavior and various of mechanical mechanisms of shale are greatly influenced by the bedding surface. To study the effects of bedding angles on the crack propagation patterns and dynamic fracture properties, the shale notched semi-circular bend (NSCB) specimens were studied by the modified split Hopkinson pressure bar (SHPB) device, three-dimensional digital image correlation (3D-DIC) system with the high-speed (HS) photography and ABAQUS finite element software. The research results showed that at the same impact velocity, the 30°, 45° and 60° beddings played an obvious deflexion effect on the shale crack propagation. However, the 0° and 90° bedding did not deflect the crack propagation. The dynamic fracture toughness of shale NSCB specimens increased with the increase of impact loading rate but the increase magnitude decreased with the higher impact rate. The kinetic energy during specimen fracture was calculated by the extracting displacement data from the 3D-DIC, and it was found that the kinetic energy accounted for less than 6% of the absorbed energy during the dynamic compression of the shale. The crack propagation characteristics of ABAQUS simulation was approximately consistent with the experimental results. It is conducive to the study of shale gas fracturing and the formation of complex seam networks in shale and it is of great research significance for the efficient extraction of shale gas. [ABSTRACT FROM AUTHOR]

Museum cultural relics represent a special material cultural heritage, and modern interpretations of them are needed in current society. Based on the catalogue data of cultural relics published by the State Administration of Cultural Heritage, this paper analyzes the continuity and intermittentness of cultural relics in time series by using the method of continuity judgment of cultural relics, analyzes the aggregation and migration of cultural relics in space by using the method of spatial analysis, and then uses cosine similarity to explain the similarity distribution in space and time. The results show that the overall distribution of cultural relics exhibits the characteristics of class aggregation, dynasty aggregation and regional aggregation. From the perspective of a time scale, cultural relics have different "life cycles", displaying continuity, intermittentness, and similarity. From the perspective of a spatial scale, the cultural relic distribution forms a small "cultural communication circle", showing aggregation, migration, and similarity. The temporal and spatial distribution of cultural relics exhibited more similar characteristics among dynasties that were closer together than those that were far away. [ABSTRACT FROM AUTHOR]

Contrastive learning techniques make it possible to pretrain a general model in a self-supervised paradigm using a large number of unlabeled remote sensing images. The core idea is to pull positive samples defined by data augmentation techniques closer together while pushing apart randomly sampled negative samples to serve as supervised learning signals. This strategy is based on the strict identity hypothesis, i.e., positive samples are strictly defined by each (anchor) sample's own augmentation transformation. However, this leads to the over-instancing of the features learned by the model and the loss of the ability to fully identify ground objects. Therefore, we proposed a relaxed identity hypothesis governing the feature distribution of different instances within the same class of features. The implementation of the relaxed identity hypothesis requires the sampling and discrimination of the relaxed identical samples. In this study, to realize the sampling of relaxed identical samples under the unsupervised learning paradigm, the remote sensing image was used to show that nearby objects often present a large correlation; neighborhood sampling was carried out around the anchor sample; and the similarity between the sampled samples and the anchor samples was defined as the semantic similarity. To achieve sample discrimination under the relaxed identity hypothesis, the feature loss was calculated and reordered for the samples in the relaxed identical sample queue and the anchor samples, and the feature loss between the anchor samples and the sample queue was defined as the feature similarity. Through the sampling and discrimination of the relaxed identical samples, the leap from instance-level features to class-level features was achieved to a certain extent while enhancing the network's invariant learning of features. We validated the effectiveness of the proposed method on three datasets, and our method achieved the best experimental results on all three datasets compared to six self-supervised methods. [ABSTRACT FROM AUTHOR]

With the escalating generation of municipal solid waste (MSW) and the increasing utilization of collection and transportation (C&T) vehicles within the MSW classification system, the associated costs and greenhouse gas (GHG) emissions from waste drop-off, as well as the C&T processes, have risen sharply. However, the mesoscopic view of the waste drop-off and C&T system is limited. Therefore, we divided the waste classification management (WCM) system into three subsystems: generation and drop-off, C&T, and disposal. Based on system dynamics theory, the logical relationships between relevant parameters in each subsystem were established. A WCM system dynamics model, which focused mainly on the drop-off and C&T processes, was constructed using Anylogic software. Using sensitivity, scenario, and uncertainty analyses, the economic impact and GHG emissions of the WCM system were analyzed in detail. The results showed that the waste drop-off and C&T processes accounted for 54.29–57.87% ($47.31 per ton) and 24.54–26.83% ($21.39–21.93 per ton) of the total cost in the whole waste management chain, respectively. GHG emissions were mainly generated in disposal facilities (116.84–257.86 kg CO 2 -eq/t), followed by C&T (19.02–20.55 kg CO 2 -eq/t) and drop-off processes (12.68–18.78 kg CO 2 -eq/t). The system cost and GHG emissions were significantly influenced by the components of the source-separated waste and operational parameters of the applied C&T vehicles. This study not only provides a basis for WCM policy formulation but also a tool for the design and optimization of waste C&T systems. • A system dynamics model was developed for waste classification management. • Collection and transportation sections cost $64.99–72.48/tMSW. • Vehicle operation significantly impacts cost and GHG emissions. • Electric vehicles have limited advantages. [ABSTRACT FROM AUTHOR]

Templated assembly techniques have been extensively used to develop various types of hemoglobin (Hb) loaded particles with improved performance. However, several instability issues must still be solved, including Hb exposure, enhanced Hb auto-oxidation, and the relatively weak binding of Hb to cross-linkers. Herein, to meet the stability requirements for novel hemoglobin-based oxygen carriers (HBOCs), hemoglobin-polydopamine particles (Hb-PDA) were fabricated using a mild process that combines the co-precipitation of Hb and an inorganic template with the spontaneous adhesion of PDA. The Hb-PDA showed uniform size distribution, chemical integrity of both Hb and PDA, high biocompatibility, and robust oxygen delivery. Our results demonstrated that the use of polydopamine as a biocompatible coating material reduced Hb leakage from the particles under both static and flow conditions, thus mitigating the toxicity associated with free Hb and strengthening the stability of Hb particles. In addition, Hb-PDA reduced HUVEC (Human Umbilical Vein Cells) oxidative injury and scavenged 85% of the available hydroxyl radicals, exhibiting its potential to act as an antioxidant for encapsulated Hb. Hb-PDA therefore shows significant promise as a cell-like structurally and functionally stable HBOCs. [ABSTRACT FROM AUTHOR]

Storage lesions in red blood cells (RBCs) hinder efficient circulation and tissue oxygenation. The absence of flow mechanics and gas exchange may contribute to this problem. To test if in vitro compensation of flow mechanics and gas exchange helps RBC recovery, three-dimensional polydimethylsiloxane (PDMS) porous structures were fabricated with a sugar mould, simulating lung alveoli. RBC suspensions were passed through the porous structure cyclically, simulating in vivo blood circulation. Acid-base indices, partial gas pressures, ions, glucose and RBC indices were analyzed. An atomic force microscope was used to investigate local mechanical properties of intact RBCs. RBCs suspensions that passed through the porous structures had a higher pH and oxygen partial pressure, and a lower potassium concentration and carbon dioxide partial pressure. Meantime they had better biochemical properties relative to static samples, namely, they exhibited a more homogenous distribution of Young's Modulus. RBCs that passed through a PDMS porous structure were healthier than static ones, giving hints to prevent RBC storage lesions. [ABSTRACT FROM AUTHOR]

Oxidative toxicity has impeded the development of haemoglobin-based oxygen carriers (HBOCs) by causing methaemoglobin (MetHb) formation and inducing oxidative stress. In our previous work, polydopamine-coated haemoglobin (Hb-PDA) nanoparticles have been designed and synthesized with the capacity to reduce oxidative toxicity. In this investigation, the mass ratio of dopamine (DA) to haemoglobin (Hb) and the pH value are found to be the primary factors that influence preparation of Hb-PDA nanoparticles. X-ray photoelectron spectroscopy showed that the catechol groups of DA play a crucial role in the modification of Hb surface. Hb-PDA nanoparticles were found to exhibit oxidative protection from hydrogen peroxide (H2O2) and the change of mitochondrial membrane potential showed that the Hb-PDA nanoparticles reduced H2O2-induced apoptosis. It is demonstrated that modification of PDA could maintain the oxygen-release capacity of Hb. These findings confirm that Hb-PDA nanoparticles possess restrained oxidative toxicity and preserve oxygen-release capacity. [ABSTRACT FROM AUTHOR]

RBCs undergo numerous changes during storage and stored RBCs may induce adverse effects, ultimately resulting in organ injury in transfusion recipients. We tested the hypothesis that the addition of SP to stored RBCs would improve the quality of the stored RBCs and mitigate liver injury after transfusion in a murine model. RBCs were harvested from C57BL/6J mice and stored for 14 days in CPDA-1 containing either a solution of SP in saline or saline alone. Haemolysis, the 24-hour posttransfusion recovery, the oxygen-carrying capacity, and the SOD activity of stored RBCs were evaluated. The plasma biochemistry, hepatic MDA level, MPO activity, IL-6, TNF-α concentrations, and histopathology were measured two hours after the transfusion of stored RBCs. Compared with RBCs stored in CPDA-1 and saline, the addition of SP to stored RBCs restored their oxygen-carrying capacity and SOD activity, reduced the AST activity, BUN concentrations, and LDH activity in the plasma, and decreased the MDA level, MPO activity, and concentrations of IL-6 and TNF-α in the liver. These data indicate that the addition of SP to RBCs during storage has a beneficial effect on storage lesions in vitro and subsequently alleviates liver injury after the transfusion of stored RBCs in vivo. [ABSTRACT FROM AUTHOR]

Endothelial activation elicited by inflammatory agents is regarded as a key event in the pathogenesis of several vascular inflammatory diseases. In the present study, the inhibitory effects and underlying mechanism of C-type natriuretic peptide (CNP) on LPS-induced endothelial activation were examined in human umbilical vein endothelial cells (HUVECs). The effect of CNP on adhesion molecule expression was assessed using quantitative real-time RT-PCR and western blotting analyses. The nuclear factor-κB (NF-κB), MAPK, and PI3K/Akt signaling pathways in LPS-stimulated HUVECs were investigated using western blotting analyses, and the production of intracellular reactive oxygen species (ROS) was measured using a fluorescence method. Pretreatment with CNP inhibited LPS-induced expression of intercellular adhesion molecule-1, vascular cell adhesion molecule-1, E-selectin, and P-selectin in a concentration-dependent manner. CNP suppressed the phosphorylation of p65 and NF-κB activation in LPS-stimulated cells. Moreover, CNP reduced ERK1/2 and p38 phosphorylation induced by LPS but not JNK. Furthermore, CNP induced Akt phosphorylation and activation of hemeoxygenase-1 (HO-1) expression. CNP significantly inhibited the production of intracellular ROS. These results suggest that CNP effectively attenuated LPS-induced endothelial activation by inhibiting the NF-κB and p38 signaling pathways, eliminating LPS-induced intracellular ROS production, and activating the PI3K/Akt/HO-1 pathway in HUVECs; thereby, demonstrating that CNP may be a potential therapeutic target for the treatment of sepsis and inflammatory vascular diseases. [ABSTRACT FROM AUTHOR]

Background: The mechanical properties of cellular microenvironments play important roles in regulating cellular functions. Studies of the molecular response of endothelial cells to alterations in substrate stiffness could shed new light on the development of cardiovascular disease. Quantitative real-time PCR is a current technique that is widely used in gene expression assessment, and its accuracy is highly dependent upon the selection of appropriate reference genes for gene expression normalization. This study aimed to evaluate and identify optimal reference genes for use in studies of the response of endothelial cells to alterations in substrate stiffness. Methodology/Principal Findings: Four algorithms, GeNormPLUS, NormFinder, BestKeeper, and the Comparative ΔCt method, were employed to evaluate the expression of nine candidate genes. We observed that the stability of potential reference genes varied significantly in human umbilical vein endothelial cells on substrates with different stiffness. B2M, HPRT-1, and YWHAZ are suitable for normalization in this experimental setting. Meanwhile, we normalized the expression of YAP and CTGF using various reference genes and demonstrated that the relative quantification varied according to the reference genes. Conclusion/Significance:: Consequently, our data show for the first time that B2M, HPRT-1, and YWHAZ are a set of stably expressed reference genes for accurate gene expression normalization in studies exploring the effect of subendothelial matrix stiffening on endothelial cell function. We furthermore caution against the use of GAPDH and ACTB for gene expression normalization in this experimental setting because of the low expression stability in this study. [ABSTRACT FROM AUTHOR]

Remote sensing images are widely used in object detection and tracking, military security, and other computer vision tasks. However, remote sensing images are often degraded by suspended aerosol in the air, especially under poor weather conditions, such as fog, haze, and mist. The quality of remote sensing images directly affect the normal operations of computer vision systems. As such, haze removal is a crucial and indispensable pre-processing step in remote sensing image processing. Additionally, most of the existing image dehazing methods are not applicable to all scenes, so the corresponding dehazed images may have varying degrees of color distortion. This paper proposes a novel atmospheric light estimation based dehazing algorithm to obtain high visual-quality remote sensing images. First, a differentiable function is used to train the parameters of a linear scene depth model for the scene depth map generation of remote sensing images. Second, the atmospheric light of each hazy remote sensing image is estimated by the corresponding scene depth map. Then, the corresponding transmission map is estimated on the basis of the estimated atmospheric light by a haze-lines model. Finally, according to the estimated atmospheric light and transmission map, an atmospheric scattering model is applied to remove haze from remote sensing images. The colors of the images dehazed by the proposed method are in line with the perception of human eyes in different scenes. A dataset with 100 remote sensing images from hazy scenes was built for testing. The performance of the proposed image dehazing method is confirmed by theoretical analysis and comparative experiments. [ABSTRACT FROM AUTHOR]

Satellite mapping of buildings and built-up areas used to be delineated from high spatial resolution (e.g., meters or sub-meters) and middle spatial resolution (e.g., tens of meters or hundreds of meters) satellite images, respectively. To the best of our knowledge, it is important to explore a deep-learning approach to delineate high-resolution semantic maps of buildings from middle-resolution satellite images. The approach is termed as super-resolution semantic segmentation in this paper. Specifically, we design a neural network with integrated low-level image features of super-resolution and high-level semantic features of super-resolution, which is trained with Sentinel-2A images (i.e., 10 m) and higher-resolution semantic maps (i.e., 2.5 m). The network, based on super-resolution semantic segmentation features is called FSRSS-Net. In China, the 35 cities are partitioned into three groups, i.e., 19 cities for model training, four cities for quantitative testing and the other 12 cities for qualitative generalization ability analysis of the learned networks. A large-scale sample dataset is created and utilized to train and validate the performance of the FSRSS-Net, which includes 8597 training samples and 766 quantitative accuracy evaluation samples. Quantitative evaluation results show that: (1) based on the 10 m Sentinel-2A image, the FSRSS-Net can achieve super-resolution semantic segmentation and produce 2.5 m building recognition results, and there is little difference between the accuracy of 2.5 m results by FSRSS-Net and 10 m results by U-Net. More importantly, the 2.5 m building recognition results by FSRSS-Net have higher accuracy than the 2.5 m results by U-Net 10 m building recognition results interpolation up-sampling; (2) from the spatial visualization of the results, the building recognition results of 2.5 m are more precise than those of 10 m, and the outline of the building is better depicted. Qualitative analysis shows that: (1) the learned FSRSS-Net can be also well generalized to other cities that are far from training regions; (2) the FSRSS-Net can still achieve comparable results to the U-Net 2 m building recognition results, even when the U-Net is directly trained using both 2-meter resolution GF2 satellite images and corresponding semantic labels. [ABSTRACT FROM AUTHOR]

Aberrant expression of microRNAs (miRNAs/miRs) plays a key role in the development of non-small cell lung cancer (NSCLC). In the present study, lower miRNA (miR)-491-5p levels and a higher forkhead box P4 (FOXP4) mRNA level were observed in NSCLC tissues and cell lines, compared to adjacent tissues and the normal human lung epithelial cell line BEAS-2B, respectively. A549 cell proliferation and migration were inhibited upon transfection of miR-491-5p mimics compared to miR-negative control (NC) mimics. In addition, compared to miR-NC mimics, overexpression of miR-491-5p decreased FOXP4 expression, while downregulation of miR-491-5p increased FOXP4 expression in A549 cells. The dual luciferase assay confirmed that the 3'untranslated region of FOXP4 was a target for miR-491-5p in A549 cells. Moreover, compared with the control short hairpin (sh)RNA, there was lower expression levels of TGF-β and its downstream targets (MMP-2 and MMP-9) in the FOXP4 shRNA group. Similarly, compared to miR-NC mimics, overexpression of miR-491-5p decreased MMP-2 and MMP-9 expression levels. In FOXP4-knockdown A549 cells, overexpression of miR-491-5p showed little effect on cell proliferation/migration. In A549 cells, overexpression of FOXP4 partially reversed the miR-491-5p mimics-induced inhibition on the cell proliferation and migration. These results may provide new insights into the role of miR-491-5p in NSCLC. [ABSTRACT FROM AUTHOR]